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 A087914 #16 Apr 18 2021 06:05:35
%S A087914 8,48,224,960,1215,3968,16128,65024,261120,1046528,4190208,16769024,
%T A087914 67092480,268402688,1073676288,4294836224
%N A087914 Numbers m such that A007947(m) = A007947(k) and A007947(m+1) = A007947(k+1), for some k < m.
%C A087914 For every k > 1, the sequence includes 4^k - 2^(k+1), with m = 2^k - 2. - _David Wasserman_, Jan 29 2004
%C A087914 a(12) <= 16769024. a(13) <= 67092480. a(14) <= 268402688. a(15) <= 1073676288. [_Donovan Johnson_, Dec 19 2008]
%e A087914 A007947(8) = A007947(2) and A007947(9) = A007947(3), so 8 is in the sequence.
%o A087914 (PARI) rad(n) = factorback(factorint(n)[, 1]); \\ A007947
%o A087914 isok(m) = {my(rm = rad(m), sm = rad(m+1)); for (k=1, m-1, if ((rad(k) == rm) && (rad(k+1) == sm), return (1)););} \\ _Michel Marcus_, Apr 05 2021
%Y A087914 Cf. A007947, A088966.
%K A087914 nonn,hard,more
%O A087914 1,1
%A A087914 _Naohiro Nomoto_, Oct 26 2003
%E A087914 a(7)-a(11) from _Donovan Johnson_, Dec 19 2008
%E A087914 Name edited by _Michel Marcus_, Apr 06 2021
%E A087914 Confirmed a(12)-a(15) and extended with a(16) by _Martin Ehrenstein_, Apr 18 2021