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A155943 Primes p such that 16*p + 1 is also prime. 5
7, 37, 61, 97, 151, 163, 181, 193, 271, 313, 331, 337, 397, 421, 487, 523, 547, 571, 643, 691, 727, 757, 853, 877, 967, 1033, 1087, 1093, 1231, 1237, 1297, 1303, 1423, 1471, 1567, 1657, 1747, 1777, 1801, 1831, 1867, 1987, 2083, 2113, 2221, 2251, 2281, 2437 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Solutions of the equation (16*n+1)' + n' = 2, where n' is the arithmetic derivative of n. [Paolo P. Lava, Oct 31 2012]

LINKS

Vincenzo Librandi, Table of n, a(n) for n = 1..1000

MATHEMATICA

Select[Prime[Range[2500]], PrimeQ[(16*# + 1)]&] (* Vincenzo Librandi, Oct 30 2012 *)

PROG

(MAGMA) [p: p in PrimesUpTo(2500)| IsPrime(16*p + 1)]; // Vincenzo Librandi, Oct 30 2012

CROSSREFS

Cf. A094407, A155942, A155941.

Sequence in context: A127313 A217561 A003521 * A078626 A093389 A093342

Adjacent sequences:  A155940 A155941 A155942 * A155944 A155945 A155946

KEYWORD

nonn,easy

AUTHOR

Vincenzo Librandi, Jan 31 2009

STATUS

approved

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Last modified November 25 20:20 EST 2020. Contains 338627 sequences. (Running on oeis4.)