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A319692 a(n) = Product_{d|n, d<n} prime(1+A001414(d)), where A001414(d) gives the sum of prime factors of d, with repetition. 2

%I #7 Oct 02 2018 17:41:11

%S 1,2,2,10,2,70,2,110,14,130,2,10010,2,190,182,1870,2,15470,2,27170,

%T 266,370,2,3233230,26,430,238,60610,2,5169710,2,43010,518,610,494,

%U 74364290,2,710,602,13394810,2,15543710,2,175010,71162,890,2,2156564410,38,76570,854,250690,2,10318490,962,38123690,994,1130,2,971341981610,2,1310,140182,1333310,1118

%N a(n) = Product_{d|n, d<n} prime(1+A001414(d)), where A001414(d) gives the sum of prime factors of d, with repetition.

%H Antti Karttunen, <a href="/A319692/b319692.txt">Table of n, a(n) for n = 1..8192</a>

%F a(n) = Product_{d|n, d<n} A000040(1+A001414(d)).

%F For all n >= 1:

%F A001221(a(n)) = A305611(n).

%o (PARI)

%o A001414(n) = ((n=factor(n))[, 1]~*n[, 2]); \\ From A001414.

%o A319692(n) = { my(m=1); fordiv(n, d, if(d<n, m *= prime(1+A001414(d)))); (m); }; \\ _Antti Karttunen_, Oct 02 2018

%Y Cf. A001414, A319693 (rgs-transform).

%Y Cf. also A319352.

%K nonn

%O 1,2

%A _Antti Karttunen_, Oct 02 2018

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Last modified August 27 09:19 EDT 2024. Contains 375468 sequences. (Running on oeis4.)