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A257648 Numbers m such that both p=2*m^2+11 and q=2*p^2+11 are prime. 0
1, 2, 3, 4, 6, 7, 8, 13, 20, 31, 52, 54, 62, 65, 70, 75, 137, 151, 153, 163, 212, 224, 281, 284, 329, 384, 419, 424, 445, 455, 489, 505, 524, 581, 593, 642, 646, 680, 706, 723, 738, 746, 775, 787, 795, 830, 841, 843, 918, 953, 970, 973, 984 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Numbers m such that both m and p=2*m^2+11 are terms in A092968. Also, both p and q are terms in A050265.

LINKS

Table of n, a(n) for n=1..53.

EXAMPLE

n=1: m=1=A092968(2) and p=13=A092968(12),

n=8: m=13=A092968(12) and p=349=A092968(127),

n=9: m=20=A092968(12) and p=811=A092968(251).

MATHEMATICA

Reap[Do[If[PrimeQ[p=2*k^2+11]&&PrimeQ[2*(p)^2+11], Sow[k]], {k, 10^3}]][[2, 1]]

CROSSREFS

Cf. A050265, A092968.

Sequence in context: A283112 A174099 A099005 * A096360 A039087 A093710

Adjacent sequences:  A257645 A257646 A257647 * A257649 A257650 A257651

KEYWORD

nonn

AUTHOR

Zak Seidov, Jul 25 2015

STATUS

approved

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Last modified June 20 09:27 EDT 2019. Contains 324234 sequences. (Running on oeis4.)