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%I A286377 #12 May 09 2017 17:37:53
%S A286377 1,2,2,60,2,2520,60,138600,2,87318000,2520,189189000,60,
%T A286377 792148896000000,138600,70756686000,2,2288271225240000,87318000,
%U A286377 944154902157667200000000,2520,20388496616888400000000,189189000,127170673342713000000,60,701323506627727183200000000,792148896000000,21149759041410320377056000000000000000,138600
%N A286377 a(n) = A278243(n^2).
%C A286377 Observation: the restricted growth sequence computed for this sequence seems to give A103391 (apart from the fact that the latter uses starting offset 1 instead of 0. Checked up to n=2048). If this holds, then A103391 works as a more practical filtering sequence (than this sequence, with its huge terms) matching for example to sequences like A286387. Compare also to A286378.
%H A286377 Antti Karttunen, <a href="/A286377/b286377.txt">Table of n, a(n) for n = 0..256</a>
%H A286377 <a href="/index/St#Stern">Index entries for sequences related to Stern's sequences</a>
%F A286377 a(n) = A278243(A000290(n)) = A278243(n^2).
%o A286377 (PARI)
%o A286377 A046523(n) = { my(f=vecsort(factor(n)[, 2], , 4), p); prod(i=1, #f, (p=nextprime(p+1))^f[i]); };  \\ This function from _Charles R Greathouse IV_, Aug 17 2011
%o A286377 A003961(n) = my(f = factor(n)); for (i=1, #f~, f[i, 1] = nextprime(f[i, 1]+1)); factorback(f); \\ This function from _Michel Marcus_
%o A286377 A260443(n) = if(n<2, n+1, if(n%2, A260443(n\2)*A260443(n\2+1), A003961(A260443(n\2))));
%o A286377 A278243(n) = A046523(A260443(n));
%o A286377 A286377(n) = A278243(n*n);
%o A286377 for(n=0, 256, write("b286377.txt", n, " ", A286377(n)));
%o A286377 (Scheme) (define (A286377 n) (A278243 (* n n)))
%Y A286377 Cf. A000290, A103391, A278243, A286374, A286378, A286387.
%K A286377 nonn
%O A286377 0,2
%A A286377 _Antti Karttunen_, May 09 2017

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