Sierpinski's triangle and the Prouhet-Thue-Morse word

The Prouhet-Tarry-Escott Problem and Generalized Thue-Morse Sequences

We present new methods of generating Prouhet-Tarry-Escott partitions of arbitrarily large regularity. One of these methods generalizes the construction of the Thue-Morse sequence to finite alphabets with more than two letters. We show how one can use such partitions to (theoretically) pour the same volume coffee from an urn into a finite number of cups so that each cup gets almost the same amount of caffeine.

Prouhet-Thue-Morse序列中的二元模式

Binary patterns in the Prouhet-Thue-Morse sequence

本文证明Prouhet-Thue-Morse序列中除两个例外单词外，所有二元模式均可作为片段出现，并识别出有限多个非平凡出现的模式。

A Matrix Related to Stern Polynomials and the Prouhet-Thue-Morse Sequence

The Stern polynomials defined by $s(0;x)=0$, $s(1;x)=1$, and for $n\geq 1$ by $s(2n;x)=s(n;x^2)$ and $s(2n+1;x)=x\,s(n;x^2)+s(n+1;x^2)$ have only 0 and 1 as coefficients. We construct an infinite lower-triangular matrix related to the coefficients of the $s(n;x)$ and show that its inverse has only 0, 1, and $-1$ as entries, which we find explicitly. In particular, the sign distribution of the entries is determined by the Prouhet-Thue-Morse sequence. We also obtain other properties of this matrix and a related Pascal-type matrix that involve the Catalan, Stirling, Fibonacci, Fine, and Padovan n…

Some identities involving Prouhet-Thue-Morse sequence and its relatives

Let $s_{k}(n)$ denote the sum of digits of an integer $n$ in base $k$. Motivated by certain identities of Nieto, and Bateman and Bradley involving sums of the form $\sum_{i=0}^{2^{n}-1}(-1)^{s_{2}(i)}(x+i)^{m}$ for $m=n$ and $m=n+1$, we consider the sequence of polynomials \begin{equation*} f_{m,n}^{\mathbf u}(x)=\sum_{i=0}^{k^{n}-1}ζ_{k}^{s_{k}(i)}(x+{\mathbf u}(i))^{m}. \end{equation*} defined for sequences ${\bf u}(i)$ satisfying a certain recurrence relation. We prove that computing these polynomials is essentially equivalent with computing their constant term and we find an explicit formu…

On formal inverse of the Prouhet-Thue-Morse sequence

Let $p$ be a prime number and consider a $p$-automatic sequence ${\bf u}=(u_{n})_{n\in\N}$ and its generating function $U(X)=\sum_{n=0}^{\infty}u_{n}X^{n}\in\mathbb{F}_{p}[[X]]$. Moreover, let us suppose that $u_{0}=0$ and $u_{1}\neq 0$ and consider the formal power series $V\in\mathbb{F}_{p}[[X]]$ which is a compositional inverse of $U(X)$, i.e., $U(V(X))=V(U(X))=X$. In this note we initiate the study of arithmetic properties of the sequence of coefficients of the power series $V(X)$. We are mainly interested in the case when $u_{n}=t_{n}$, where $t_{n}=s_{2}(n)\pmod{2}$ and ${\bf t}=(t_{n})_…

Arithmetic properties of coefficients of power series expansion of $\prod_{n=0}^{\infty}\left(1-x^{2^{n}}\right)^{t}$ (with an Appendix by Andrzej Schinzel)

Let $F(x)=\prod_{n=0}^{\infty}(1-x^{2^{n}})$ be the generating function for the Prouhet-Thue-Morse sequence $((-1)^{s_{2}(n)})_{n\in\N}$. In this paper we initiate the study of the arithmetic properties of coefficients of the power series expansions of the function $$ F_{t}(x)=F(x)^{t}=\sum_{n=0}^{\infty}f_{n}(t)x^{n}. $$ For $t\in\N_{+}$ the sequence $(f_{n}(t))_{n\in\N}$ is the Cauchy convolution of $t$ copies of the Prouhet-Thue-Morse sequence. For $t\in\Z_{<0}$ the $n$-th term of the sequence $(f_{n}(t))_{n\in\N}$ counts the number of representations of the number $n$ as a sum of powers of…