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A319356 a(n) = Product_{d|n, d<n} prime(1+A003415(d)), where A003415(d) gives arithmetic derivative of d. 4
1, 2, 2, 6, 2, 18, 2, 66, 6, 18, 2, 2574, 2, 18, 18, 2706, 2, 3978, 2, 3762, 18, 18, 2, 6226506, 6, 18, 102, 5742, 2, 306774, 2, 370722, 18, 18, 18, 203956038, 2, 18, 18, 14961474, 2, 631098, 2, 8514, 7038, 18, 2, 168047170434, 6, 10602, 18, 10494, 2, 33626034, 18, 32252814, 18, 18, 2, 2529917014482, 2, 18, 9486, 155332518, 18, 1418742, 2, 14058, 18, 1219914, 2 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Antti Karttunen, Table of n, a(n) for n = 1..8192

FORMULA

a(n) = Product_{d|n, d<n} A000040(1+A003415(d)).

For all n >= 1:

A001221(a(n)) = A319685(n).

A056239(A064989(a(n)) = A319683(n).

PROG

(PARI)

A003415(n) = {my(fac); if(n<1, 0, fac=factor(n); sum(i=1, matsize(fac)[1], n*fac[i, 2]/fac[i, 1]))}; \\ From A003415

A319356(n) = { my(m=1); fordiv(n, d, if(d<n, m *= prime(1+A003415(d)))); (m); };

CROSSREFS

Cf. A003415, A319357 (rgs-transform).

Sequence in context: A211776 A325248 A036655 * A098792 A061057 A038667

Adjacent sequences:  A319353 A319354 A319355 * A319357 A319358 A319359

KEYWORD

nonn

AUTHOR

Antti Karttunen, Oct 02 2018

STATUS

approved

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Last modified October 7 10:36 EDT 2022. Contains 357270 sequences. (Running on oeis4.)