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Numbers k such that both p1=2k+3 and p2=4k+5 are primes.
8

%I #17 Jan 27 2024 10:33:01

%S 0,2,8,14,17,38,47,68,77,98,104,113,134,152,164,167,182,188,218,248,

%T 272,287,299,302,308,329,344,362,404,413,437,467,482,497,503,533,584,

%U 617,638,647,698,713,728,764,803,812,827,878,932,1004,1013,1043,1064,1067

%N Numbers k such that both p1=2k+3 and p2=4k+5 are primes.

%C p1 in A005382, p2 in A005383.

%H Karl-Heinz Hofmann, <a href="/A105610/b105610.txt">Table of n, a(n) for n = 1..10000</a>

%t Select[Range[0,1067], PrimeQ[2#+3]&&PrimeQ[4#+5]&] (* _James C. McMahon_, Jan 26 2024 *)

%o (Python)

%o from sympy import isprime

%o print([ k for k in range(0,1068) if isprime(2*k+3) and isprime(4*k+5)])

%o # _Karl-Heinz Hofmann_, Jan 27 2024

%Y Cf. A005382, A005383.

%Y Equals A123998 minus 1.

%K nonn

%O 1,2

%A _Zak Seidov_, Apr 15 2005