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%I #14 Nov 22 2016 21:48:28
%S 2,4,6,8,12,6,12,12,24,30,32,6,30,12,48,24,60,6,12,72,6,48,60,60,12,
%T 30,24,72,30,30,128,60,30,60,60,24,6,12,120,30,180,30,192,6,60,72,12,
%U 96,60,30,60,240,12,180,30,120,120,48,6,30,12,60,60,120,6,30,12,12,60,60,30,360,48,30,60,384,210,6,30,30,420,6,432,30,120,60,180,6,210,48
%N Least number with the prime signature of prime(n)+1.
%H Antti Karttunen, <a href="/A278228/b278228.txt">Table of n, a(n) for n = 1..10000</a>
%F a(n) = A046523(A000040(n)+1).
%t 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 (Scheme) (define (A278228 n) (A046523 (+ 1 (A000040 n))))
%Y Cf. A000040, A046523.
%Y Cf. A174801 (positions of terms <= 6).
%Y Cf. also A278227, A278229, A278230.
%K nonn
%O 1,1
%A _Antti Karttunen_, Nov 19 2016
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