S000795


Prime numbers that are the sum of consecutive 9-gonal numbers.

79, 419, 619, 1033, 1429, 1451, 3433, 4057, 4259, 5531, 6361, 6971, 7459, 8161, 12433, 14411, 16691, 19139, 20521, 25321, 31357, 36433, 37357, 44771, 46639, 48049, 48731, 52859, 53899, 70201, 71719, 94057, 97571, 107881, 110629, 115499, 119419, 128291

1

S000795

Terms are the sum of 2, 3, or 6 consecutive 9-gonal numbers.

T. D. Noe, Plot of 1000 terms

T. D. Noe, Table of 1000 terms

Wikipedia, Polygonal number

(Mma) nn = 400; f = 9; s = Table[k ((f - 2) k - (f - 4))/2, {k, nn}]; t = Table[Select[Plus @@@ Partition[s, n, 1], PrimeQ], {n, 6}]; mx = Min[Select[Max /@ Rest[t], # > 0 &]]; Select[Union[Flatten[t]], # <= mx &]

Cf. A163251 (squares), S000790-S000799.

nonn

T. D. Noe, Dec 11 2015

© Tony D Noe 2014-2015