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.

A112622 If p^b(p,n) is the highest power of the prime p dividing n, then a(n) = product_{p|n} b(p,n)^b(p,n).

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%I A112622 #19 May 28 2017 09:14:19
%S A112622 1,1,1,4,1,1,1,27,4,1,1,4,1,1,1,256,1,4,1,4,1,1,1,27,4,1,27,4,1,1,1,
%T A112622 3125,1,1,1,16,1,1,1,27,1,1,1,4,4,1,1,256,4,4,1,4,1,27,1,27,1,1,1,4,1,
%U A112622 1,4,46656,1,1,1,4,1,1,1,108,1,1,4,4,1,1,1,256,256,1,1,4,1,1,1,27,1,4,1,4,1,1,1,3125,1,4,4,16,1,1,1,27,1
%N A112622 If p^b(p,n) is the highest power of the prime p dividing n, then a(n) = product_{p|n} b(p,n)^b(p,n).
%C A112622 a(1) = 1 (empty product).
%H A112622 Antti Karttunen, <a href="/A112622/b112622.txt">Table of n, a(n) for n = 1..10000</a>
%e A112622 45 = 3^2 * 5^1. So a(45) = 2^2 * 1^1 = 4.
%e A112622 72 = 2^3 * 3^2. So a(72) = 3^3 * 2^2 = 108.
%t A112622 f[n_] := Block[{fi = Last@Transpose@FactorInteger@n}, Times @@ (fi^fi)]; Rest@Array[f, 93] (* _Robert G. Wilson v_ *)
%o A112622 (PARI) a(n)=local(v,r,i);v=factorint(n);r=1;for(i=1,matsize(v)[1],r*=v[i,2]^v[i,2]);r (Herrgesell)
%Y A112622 Cf. A112621, A112624.
%K A112622 nonn,mult
%O A112622 1,4
%A A112622 _Leroy Quet_, Dec 25 2005
%E A112622 More terms from _Robert G. Wilson v_ and Lambert Herrgesell (zero815(AT)googlemail.com), Dec 27 2005
%E A112622 Corrected the starting offset, data section extended to 105 terms - _Antti Karttunen_, May 28 2017