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A344580 Numbers k such that A101203(k) is prime. 2
4, 5, 6, 7, 8, 15, 18, 19, 26, 33, 44, 50, 64, 69, 74, 115, 138, 139, 150, 151, 161, 170, 208, 213, 218, 232, 233, 237, 246, 258, 275, 289, 290, 303, 309, 310, 311, 333, 334, 340, 352, 353, 360, 369, 376, 405, 412, 441, 483, 489, 495, 502, 503, 507, 514, 529, 610, 615, 633, 638, 645, 648, 658 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Numbers k such that the sum of nonprimes <= k is prime.

If p is prime then p is a member if and only if p-1 is a member.

LINKS

Robert Israel, Table of n, a(n) for n = 1..10000

EXAMPLE

a(3) = 6 is a member because A101203(6) = 1+4+6 = 11 is prime.

MAPLE

s:= proc(n) option remember; if isprime(n) then procname(n-1) else procname(n-1)+ n fi end proc:

s(1):= 1:

select(n -> isprime(s(n)), [$1..1000]);

CROSSREFS

Cf. A101203, A228102.

Sequence in context: A050038 A285218 A059709 * A071623 A274552 A280682

Adjacent sequences:  A344577 A344578 A344579 * A344581 A344582 A344583

KEYWORD

nonn

AUTHOR

J. M. Bergot and Robert Israel, May 23 2021

STATUS

approved

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Last modified January 24 09:13 EST 2022. Contains 350534 sequences. (Running on oeis4.)