A285790 Primes equal to a hexagonal number plus 1.

2, 7, 29, 67, 191, 277, 379, 631, 947, 1129, 1327, 2017, 2557, 2851, 4561, 4951, 5779, 6217, 8647, 9181, 12721, 13367, 14029, 15401, 16111, 17579, 20707, 21529, 22367, 24091, 24977, 31627, 36857, 37951, 42487, 43661, 44851, 47279, 53629, 58997, 64621, 66067

Offset

1,1

Comments

Apart from the leading 2 the same as A176616. - R. J. Mathar, Apr 27 2017

Primes in A130883. - Omar E. Pol, Apr 27 2017

Links

Colin Barker, Table of n, a(n) for n = 1..1000

Mathematica

Select[PolygonalNumber[6, Range[200]]+1, PrimeQ] (* Harvey P. Dale, Jun 16 2022 *)

Prog

(PARI) pg(m, n) = (n^2*(m-2)-n*(m-4))/2 \\ n-th m-gonal number
maxk=300; L=List(); for(k=1, maxk, if(isprime(p=pg(6, k) + 1), listput(L, p))); Vec(L)

Crossrefs

Cf. A000040, A000384, A002496, A055469, A285789, A285791, A176616, A285792.

Sequence in context: A359633 A339868 A181758 * A083016 A062064 A158024

Adjacent sequences: A285787 A285788 A285789 * A285791 A285792 A285793

Keyword

nonn

Author

Colin Barker, Apr 26 2017

Status

approved