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%I #9 Nov 22 2016 21:49:37
%S 1,2,2,2,2,2,6,2,2,2,2,6,2,6,2,2,6,6,2,2,2,6,6,2,6,2,6,2,6,2,2,6,6,6,
%T 2,8,6,2,2,6,2,12,6,2,2,2,30,2,6,2,6,30,2,2,2,2,6,6,2,2,6,30,6,2,2,2,
%U 6,2,6,2,6,6,6,6,6,2,6,6,6,30,6,6,2,12,2,2,6,6,2,6,6,30,2,2,6,2,6,6,6,2,2,30,2,6,6,6,6,6,6,6,6,6,6,2,2,6,30,6,6
%N a(n) = least number with the same prime signature as n + (n+1)^2.
%C Almost all terms seem to be primorials, 4848 of the first 5000, in other words, most terms of A028387 (in the same range) are squarefree.
%H Antti Karttunen, <a href="/A278247/b278247.txt">Table of n, a(n) for n = 0..5000</a>
%F a(n) = A046523(A028387(n)).
%o (Scheme) (define (A278247 n) (A046523 (A028387 n)))
%Y Cf. A028387, A046523.
%Y Cf. also A278246, A278251, A278253, A278255.
%K nonn
%O 0,2
%A _Antti Karttunen_, Nov 21 2016
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