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 A278227 #14 Nov 22 2016 21:48:17
%S A278227 1,2,4,6,6,12,16,12,6,12,30,36,24,30,6,12,6,60,30,30,72,30,6,24,96,36,
%T A278227 30,6,72,48,60,30,24,30,12,60,60,48,6,12,6,180,30,192,36,60,210,30,6,
%U A278227 60,24,30,240,24,256,6,12,120,60,120,30,12,60,30,120,12,210,240,6,60,96,6,30,60,120,6,12,180,144,120,30,420,30,432,30,30,192,120,60,210
%N A278227 Least number with the prime signature of prime(n)-1.
%H A278227 Antti Karttunen, <a href="/A278227/b278227.txt">Table of n, a(n) for n = 1..10000</a>
%F A278227 a(n) = A046523(A000040(n)-1).
%t A278227 Table[Times @@ MapIndexed[(Prime@ First@ #2)^#1 &, #] &@ If[Length@ # == 1 && #[[1, 1]] == 1, {0}, Reverse@ Sort@ #[[All, -1]]] &@ FactorInteger[Prime@ n - 1], {n, 120}] (* _Michael De Vlieger_, Nov 21 2016 *)
%o A278227 (Scheme) (define (A278227 n) (A046523 (+ -1 (A000040 n))))
%Y A278227 Cf. A000040, A046523.
%Y A278227 Cf. also A278228, A278229, A278230.
%K A278227 nonn
%O A278227 1,2
%A A278227 _Antti Karttunen_, Nov 19 2016