%I A003959
%S A003959 1,3,4,9,6,12,8,27,16,18,12,36,14,24,24,81,18,48,20,54,32,36,24,108,36,
%T A003959 42,64,72,30,72,32,243,48,54,48,144,38,60,56,162,42,96,44,108,96,72,48,
%U A003959 324,64,108,72,126,54,192,72,216,80,90,60,216,62,96,128,729,84,144,68
%N A003959 If n = Product p(k)^e(k) then a(n) = Product (p(k)+1)^e(k), a(1) = 1.
%C A003959 Completely multiplicative.
%H A003959 Daniel Forgues, <a href="b003959.txt">Table of n, a(n) for n=1..100000</
a>
%F A003959 If n = Product p(k)^e(k) then a(n) = Product (p(k)+1)^e(k), a(1) = 1.
%F A003959 Multiplicative with a(p^e) = (p+1)^e. - David W. Wilson (davidwwilson(AT)comcast.net),
Aug 01, 2001.
%o A003959 (PARI) a(n)=if(n<1,0,direuler(p=2,n,1/(1-X-p*X))[n]) (from R. Stephan)
%Y A003959 Apart from initial terms, same as A064478. Cf. A003958.
%Y A003959 Cf. A063441.
%Y A003959 Adjacent sequences: A003956 A003957 A003958 this_sequence A003960 A003961
A003962
%K A003959 nonn,easy,nice,mult,new
%O A003959 1,2
%A A003959 Marc LeBrun (mlb(AT)well.com)
%E A003959 Definition reedited (with formula) by Daniel Forgues (squid(AT)zensearch.com),
Nov 17 2009
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