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A276264 Centered 25-gonal primes. 1
151, 251, 701, 1951, 3001, 4751, 10151, 12401, 16651, 19501, 28201, 29401, 33151, 38501, 39901, 45751, 56951, 63901, 65701, 81001, 87151, 95701, 104651, 114001, 136501, 144451, 147151, 158201, 178501, 181501, 193751, 219451, 232901, 257401, 275651, 290701, 318001, 322001 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Primes of the form (25*k^2 + 25*k + 2)/2.

Numbers k such that (25*k^2 + 25*k + 2)/2 is prime: 3, 4, 7, 12, 15, 19, 28, 31, 36, 39, 47, 48, 51, 55, 56, 60, 67, 71, 72, 80, 83, 87, 91, ...

LINKS

Robert Israel, Table of n, a(n) for n = 1..10000

OEIS Wiki, Centered polygonal numbers

Eric Weisstein's World of Mathematics, Centered Polygonal Number

Index entries for sequences related to centered polygonal numbers

MAPLE

select(isprime, [seq((25*k^2+25*k+2)/2, k=1..200)]); # Robert Israel, Sep 01 2016

MATHEMATICA

Intersection[Table[(25 k^2 + 25 k + 2)/2, {k, 0, 1000}], Prime[Range[28000]]]

PROG

(PARI) lista(nn) = for(n=1, nn, if(isprime(p=(25*n^2 + 25*n + 2)/2), print1(p, ", "))); \\ Altug Alkan, Aug 26 2016

CROSSREFS

Cf. A000040, A262221.

Cf. centered k-gonal primes listed in A276261.

Sequence in context: A334931 A059858 A152310 * A070182 A100200 A142575

Adjacent sequences:  A276261 A276262 A276263 * A276265 A276266 A276267

KEYWORD

nonn

AUTHOR

Ilya Gutkovskiy, Aug 26 2016

STATUS

approved

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Last modified August 11 18:37 EDT 2020. Contains 336428 sequences. (Running on oeis4.)