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A120289 Primes p such that p divides numerator of Sum[1/Prime[k]^Prime[n],{k,1,n-1}]. 2
5, 19, 47, 79, 109 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..5.

EXAMPLE

a(1) = 5 because prime 5 divides 275 = numerator[1/2^5 + 1/3^5].

Sum[1/Prime[k]^Prime[n],{k,1,n-1}] begins

n=2 1/2^3 = 1/8

n=3 1/2^5 + 1/3^5 = 275/7776

n=4 1/2^7 + 1/3^7 + 1/5^7 = 181139311/21870000000

n=5 1/2^11 + 1/3^11 + 1/5^11 + 1/7^11 = 17301861338484245234233/35027750054222100000000000

CROSSREFS

Cf. A119722.

Sequence in context: A146736 A176358 A045458 * A293457 A243895 A024191

Adjacent sequences:  A120286 A120287 A120288 * A120290 A120291 A120292

KEYWORD

frac,nonn

AUTHOR

Alexander Adamchuk, Jul 08 2006

STATUS

approved

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Last modified June 23 18:45 EDT 2021. Contains 345402 sequences. (Running on oeis4.)