pith. sign in

arxiv: 1901.04842 · v1 · pith:HQAEAMEJnew · submitted 2019-01-04 · 🧮 math.NT

An Identity Motivated by an Amazing Identity of Ramanujan

classification 🧮 math.NT
keywords identityinftyramanujanamazinggeneralmotivatedpowersequences
0
0 comments X
read the original abstract

Ramanujan stated an identity to the effect that if three sequences $\{a_n\}$, $\{b_n\}$ and $\{c_n\}$ are defined by $r_1(x)=:\sum_{n=0}^{\infty}a_nx^n$, $r_2(x)=:\sum_{n=0}^{\infty}b_nx^n$ and $r_3(x)=:\sum_{n=0}^{\infty}c_nx^n$ (here each $r_i(x)$ is a certain rational function in $x$), then \[ a_n^3+b_n^3-c_n^3=(-1)^n, \hspace{25pt} \forall \,n \geq 0. \] Motivated by this amazing identity, we state and prove a more general identity involving eleven sequences, the new identity being "more general" in the sense that equality holds not just for the power 3 (as in Ramanujan's identity), but for each power $j$, $1\leq j \leq 5$.

This paper has not been read by Pith yet.

discussion (0)

Sign in with ORCID, Apple, or X to comment. Anyone can read and Pith papers without signing in.