A157934 Numbers m such that m^2+1 is prime and m^2-7 = prevprime(m^2) (= A007917(m^2)).

54, 66, 90, 156, 240, 270, 306, 474, 570, 576, 636, 750, 780, 1080, 1320, 1350, 2034, 2154, 2406, 2700, 2760, 3204, 3240, 3306, 3480, 3516, 3756, 3774, 3984, 4056, 4086, 4140, 4146, 4176, 4716, 4734, 4794, 5154, 5370, 5424, 5550, 5664, 5700, 5850, 5856

Offset: 1

Author

M. F. Hasler, Mar 18 2009

Keywords

• nonn

Comments

The corresponding primes are listed in A157183 resp. A157935.

Links

• Harvey P. Dale, Table of n, a(n) for n = 1..1000

Crossrefs

Cf. A157183, A028883, A028882, A005574, A157935.

Programs

Mathematica

Select[Range[6000],PrimeQ[#^2+1]&&#^2-7==NextPrime[#^2,-1]&] (* Harvey P. Dale, Mar 19 2020 *)

PARI

forstep(m=2,9999,2, isprime(m^2+1) & precprime(m^2)==m^2-7 & print1(m,","))