cp's OEIS Frontend

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.

A332461 a(n) = Product_{d|n, d>1} A000040(A297113(d)), where A000040(n) gives the n-th prime, and A297113(n) = the excess of n plus the index of the largest dividing prime (A046660 + A061395).

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%I A332461 #9 Feb 22 2020 18:02:47
%S A332461 1,2,3,6,5,18,7,30,15,50,11,270,13,98,75,210,17,450,19,1050,147,242,
%T A332461 23,9450,35,338,105,3234,29,11250,31,2310,363,578,245,47250,37,722,
%U A332461 507,57750,41,43218,43,9438,2625,1058,47,727650,77,2450,867,17238,53,22050,605,210210,1083,1682,59,8268750,61,1922,8085,30030
%N A332461 a(n) = Product_{d|n, d>1} A000040(A297113(d)), where A000040(n) gives the n-th prime, and A297113(n) = the excess of n plus the index of the largest dividing prime (A046660 + A061395).
%H A332461 Antti Karttunen, <a href="/A332461/b332461.txt">Table of n, a(n) for n = 1..16384</a>
%H A332461 <a href="/index/Pri#prime_indices">Index entries for sequences computed from indices in prime factorization</a>
%F A332461 a(n) = Product_{d|n, d>1} A000040(A297113(d)).
%F A332461 a(p) = p for all primes p.
%F A332461 For all n >= 0, a(2^n) = A002110(n).
%F A332461 For all n >= 1:
%F A332461 A046523(a(n)) = A324202(n).
%F A332461 A048675(a(n)) = A156552(n).
%F A332461 A097248(a(n)) = A332462(n).
%o A332461 (PARI)
%o A332461 A297113(n) = if(1==n, 0, (primepi(vecmax(factor(n)[, 1])) + (bigomega(n)-omega(n))));
%o A332461 A332461(n) = if(1==n,1, my(m=1); fordiv(n,d,if(d>1, m *= prime(A297113(d)))); (m));
%Y A332461 Cf. A000040, A002110, A046660, A046523, A048675, A061395, A097248, A156552, A297113, A324202, A332462.
%K A332461 nonn
%O A332461 1,2
%A A332461 _Antti Karttunen_, Feb 22 2020