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%I #10 Jan 06 2021 17:48:16
%S 1,3,5,15,9,13,11,75,35,25,15,65,17,31,43,375,21,91,27,125,53,43,29,
%T 325,99,49,245,155,35,95,39,1875,73,61,97,455,41,79,83,625,45,121,51,
%U 215,301,85,57,1625,143,275,103,245,59,637,133,775,133,103,65,475,69,115,371,9375,151,173,71,305,143,245,77,2275,81,121
%N a(n) = A337544(A003961(n)).
%C First negative term is a(510510) = -686785. See A001276.
%H Antti Karttunen, <a href="/A340194/b340194.txt">Table of n, a(n) for n = 1..16383</a>
%H <a href="/index/Pri#prime_indices">Index entries for sequences computed from indices in prime factorization</a>
%F a(n) = A337544(A003961(n)) = A083254(A003961(A003961(n))).
%o (PARI)
%o A003961(n) = my(f = factor(n)); for (i=1, #f~, f[i, 1] = nextprime(f[i, 1]+1)); factorback(f);
%o A083254(n) = (2*eulerphi(n)-n);
%o A340194(n) = A083254(A003961(A003961(n)));
%Y Cf. A001276, A003961, A003972, A083254, A337544.
%K sign
%O 1,2
%A _Antti Karttunen_, Dec 31 2020
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