cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A235399 Numbers which are the digital sum of the cube of some prime.

This page as a plain text file.
%I A235399 #38 Jul 19 2024 08:46:40
%S A235399 8,9,10,17,19,26,28,35,37,44,46,53,55,62,64,71,73,80,82,89,91,98,100,
%T A235399 107,109,116,118,125,127,134,136,143,145,152,154,161,163,170,172,179,
%U A235399 181,188,190,197,199,206,208,215,217,224,226,233,235,242,244,251,253
%N A235399 Numbers which are the digital sum of the cube of some prime.
%C A235399 A235398 sorted and duplicates removed.
%F A235399 Conjecture: for n > 4, a(n) = a(n-2) + 9 = A056020(n).
%F A235399 Conjecture: a(n) = (1/4)*(-1)^n*(9*(-1)^n*(2*n-1) + 5), n >= 3. - _Bill McEachen_, Feb 13 2021
%t A235399 Total[IntegerDigits[#]] & /@ (Prime[Range[5000000]]^3) // Union (* The program generates the first 39 terms of the sequence. To generate more, increase the Range constant. *) (* _Harvey P. Dale_, Sep 19 2021 *)
%o A235399 (PARI) list(maxx)={v=List();n=2; while(n<=maxx,q=n^3;summ=sumdigits(q);
%o A235399 if(setsearch(v,summ)<1,listput(v,summ));n=nextprime(n+1));vecsort(v,,8) ;} \\ _Bill McEachen_, Jan 29 2014
%Y A235399 Cf. A235398, A004164, A007953, A123157.
%K A235399 nonn,base
%O A235399 1,1
%A A235399 _Antonio GraciĆ” Llorente_, Jan 09 2014
%E A235399 a(37)-a(57) from _Lars Blomberg_, Feb 10 2016