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.
%I A100970 #19 Jul 01 2025 10:33:34 %S A100970 1836,6318,6622,10530,14500,14739,17655,18550,25398,25956,30562,39215, %T A100970 39325,50875,51429,52887,55611,56420,58548,59731,60604,72358,74620, %U A100970 76581,78780,81370,84180,85949,103350,103788,108750,112914,118233 %N A100970 Integers that are Rhonda numbers to base 8. %C A100970 See A099542 for definition of Rhonda numbers and some links. %H A100970 Reinhard Zumkeller, <a href="/A100970/b100970.txt">Table of n, a(n) for n = 1..1000</a> %H A100970 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/RhondaNumber.html">Rhonda Number</a> %H A100970 Wikipedia, <a href="http://www.wikipedia.org/wiki/Octal">Octal</a> %e A100970 Product of base 8 digits of 1836 is 3*4*5*4=240 and sum of prime factors of 1826 is 2*2+3*3+17=30 and 240=8*30. %t A100970 rhda8Q[n_]:=Times@@IntegerDigits[n,8]==8*Total[Times@@@FactorInteger[n]]; Select[Range[120000],rhda8Q] (* _Harvey P. Dale_, Jul 10 2021 *) %o A100970 (Haskell) %o A100970 a100970 n = a100970_list !! (n-1) %o A100970 a100970_list = filter (rhonda 8) a255805_list %o A100970 -- Function rhonda as in A099542. %o A100970 -- _Reinhard Zumkeller_, Mar 08 2015 %Y A100970 Cf. Rhonda numbers to other bases: A100968 (base 4), A100969 (base 6), A100973 (base 9), A099542 (base 10), A100971 (base 12), A100972 (base 14), A100974 (base 15), A100975 (base 16), A255735 (base 18), A255732 (base 20), A255736 (base 30), A255731 (base 60), see also A255872. %Y A100970 Cf. A001414, A027746, A007094, subsequence of A255805. %Y A100970 Column k=3 of A291925. %K A100970 easy,nonn,base %O A100970 1,1 %A A100970 Mark Hudson (mrmarkhudson(AT)hotmail.com), Nov 24 2004