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A136366 Numbers k such that A024530(k) is prime. 6
3, 4, 5, 10, 21, 31, 55, 77, 121, 135, 148, 192, 425, 570, 612, 649, 1293, 2326, 3646 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..19.

MATHEMATICA

f=0; Do[ p=Prime[n]; f=f + (-1)^(n+1)*1/p; g=Numerator[f] ; If[ PrimeQ[g], Print[ {n, g} ] ], {n, 1, 150} ]

CROSSREFS

Cf. A024530 = Numerator of Sum_{k=1..n} (-1)^k / prime(k). Cf. A136365, A136367, A136368, A136369, A136370, A136371.

Sequence in context: A170926 A122413 A297661 * A123820 A261903 A133320

Adjacent sequences:  A136363 A136364 A136365 * A136367 A136368 A136369

KEYWORD

more,nonn

AUTHOR

Alexander Adamchuk, Dec 27 2007

EXTENSIONS

a(12)-a(16) from Alexander Adamchuk, Sep 15 2010

a(17)-a(19) from Robert Price, Aug 27 2019

STATUS

approved

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Last modified February 26 09:05 EST 2020. Contains 332277 sequences. (Running on oeis4.)