Hi, I am

Siddhartha Mahajan

Verifiability across domains.

Software Engineer at RedGraphs and AI researcher based in Delhi. I build NLP and backend systems and work on AI-assisted mathematics, with a focus on traceable evidence, reproducible results, and formal verification. Previously a Research Fellow at Lossfunk, with research experience in ECG classification, parameter-efficient fine-tuning, and molecular simulations.

Siddhartha Mahajan

Featured Projects

CAISc 2026 Verifier API

Automated verification and scoring for five problems in mathematics, computer science, and computational biology. Built constraint validation, scoring, and percentile rankings for the conference's Verifiable Problems Track.

FastAPI PostgreSQL Docker

Reinforcement Learning Pipeline

Supervised fine-tuning and GRPO with LoRA on Qwen using MedMCQA. Implemented rewards for answer correctness and structured outputs, and evaluated baseline, SFT, and GRPO checkpoints.

Qwen LoRA GRPO MedMCQA

Long-Legged A: An Exact Formula

How many regions can overlapping A-shaped figures create? Established the exact formula for constrained long-legged A arrangements, with a visual proof, rational certificates through n=16, and reproducible verification.

Extremal Geometry Exact Certificates Lean 4

Lollipop Crossing Bounds

Co-authored a two-graph approach to Neil Sloane's lollipop problem with Paras Chopra. Closed Paulsen's remaining gaps through n=17 and determined the exact value aL(19)=1076.

Combinatorics Extremal Graphs Preprint

Work Experience

RedGraphs logo
Software Engineer
RedGraphs Mar 2026 - Present

Build NLP and backend pipelines that extract company relationships from regulatory filings, financial disclosures, and public information. Develop entity resolution and evaluation workflows for precision, recall, and evidence traceability, and work on backend performance, observability, and production reliability with AWS and PostgreSQL.

NLP Entity Resolution AWS PostgreSQL
Lossfunk
Research Fellow
Lossfunk Mar 2026 - Aug 2026
Lossfunk

Worked on AI-assisted mathematics across combinatorics, integer sequences, and formal verification. Co-authored research refining bounds for Neil Sloane's lollipop problem, developed exact results and computational certificates for OEIS sequences, and formalized results in Lean 4 and Mathlib with an emphasis on reproducibility and verifiability.

AI for Math Lean 4 Mathlib OEIS
CAISc 2026
Organizing Committee
CAISc 2026 2026
BITS Pilani

Helped organize the Conference for AI Scientists, focused on AI-assisted scientific discovery. Contributed to the Verifiable Problems Track and the infrastructure for evaluating submissions in mathematics, computer science, and computational biology.

AI Scientists Verifiable Track OpenReview
Jamun logo
AI Consultant
Amogha AI Technologies / Jamun Nov 2025 - Jun 2026

Worked on NLP pipelines and conversational AI for a voice-first mental health support application, using RAG, ChromaDB, and Docker with a focus on experimentation and evaluation.

RAG SentenceTransformers ChromaDB Docker
SBILab
Research Associate
SBILab, IIIT-Delhi Aug 2025 - Feb 2026
IIITD

Worked with Prof. Anubha Gupta on parameter-efficient fine-tuning (PEFT) and LoRA extensions for custom Vision Transformers trained on over 10 million ECGs.

Healthcare AI ViT LoRA PyTorch
SBILab
Research Assistant
SBILab, IIIT-Delhi Mar 2025 - Aug 2025
IIITD

Developed ECG-based subclass classification for cardiovascular diseases using signal processing. Conducted a review of risk calculators for Multiple Myeloma staging.

Healthcare AI Transformers Signal Processing
IISc
Research Intern
IISc Physics Dept. Jun 2024 - Jul 2024

Under Prof. Prabal Maiti, researched binding affinities in antibody-antigen binding using ChimeraX, Modeller, and GROMACS for MD simulations.

GROMACS MD Simulations ChimeraX
Beyond Exams
Machine Learning Intern
Beyond Exams May 2022 - Nov 2022

Built a ML model to classify educational YouTube videos. Handled pipeline: scraping (YouTube API), cleaning (BeautifulSoup), and modeling (ML.NET/C#).

ML.NET C# Web Scraping

Math Stuff

Sequence work 09 sequences

Proofs, exact values, and useful corrections

Proof pages and a compact ledger of published contributions, credited work, and drafts under review.

Full proof pages

Visual explanations, manuscripts, exact certificates, and reproducible verification.

Published on OEIS 06 records

Approved contributions and research credited in OEIS records or their revision histories.

Contribution history
A389624 exact values · joint work

Regions cut by lollipops

With Paras Chopra, closed Paulsen's remaining gaps through n=17 and at n=19, using a two-graph refinement of the crossing obstruction.

a(8), a(9), a(11)–a(17) a(19) = 1076
A286874 exact values · theorem

Binary 2-cover-free families

Proved two exact values, tightened the open n=16 interval, and added a private-chain upper bound that works in every dimension.

a(15) = 42 48 ≤ a(16) ≤ 54 a(17) = 68

Further contributions

identifications, exact values, corrections, and checks
A000758 · identification
Heights of rooted plane trees

Identified the statistic, proved three exact identities, and supplied the approved b-file through n=1000.

A273354 · exact value
Common square-and-cube sums

Proved the exact value of a(3) by exhaustive minimality checking and added a constructive upper bound for a(4).

A055397 · correction
Maximum-density still lifes

Corrected two carried terms from 301, 352 to a(24)=302 and a(26)=353, against Chu–Stuckey's published tables.

A175554 · verification
Hamiltonian decompositions of K11

Added an independent double-counting check of Mutoh's value a(5)=905,697,107,804,160, using the count for the complement of a fixed cycle.

Publications

A Two-Graph Refinement of Paulsen's Lollipop Bounds

Siddhartha Mahajan and Paras Chopra
arXiv:2606.06064 [math.CO] (2026)

Recasts the lollipop crossing problem through two interacting extremal graphs, closing Paulsen's remaining gaps through n=17 and determining aL(19)=1076.

View manuscript

Predicting Efficacy of Antiseizure Medication Treatment with Machine Learning Algorithms

Mahima Kaushik, Bibhu Biswal, Siddhartha Mahajan et al.
Epilepsy Research, Volume 205 (2024)

Conducted predictive modeling for anti-epileptic drug outcomes using patient data. Utilized six Machine Learning algorithms, achieving over 70% accuracy in predicting drug responses in the North Indian population.

View DOI

Education

CIC Logo

Cluster Innovation Centre

Bachelor of Technology (B.Tech)
2021 - 2025 • CGPA: 8.8/10

Focus: IT & Mathematical Innovations, Computational Biology.

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