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A121089 Numbers n such that f(n), f(n+1) and f(n+2) are prime, f(m)=72*m^2+7. 1
9, 24, 169, 1479, 2964, 3039, 3299, 4084, 4474, 5534, 5574, 6449, 7359, 7409, 7529, 10789, 10879, 10994, 13819, 14324, 18574, 19709, 20329, 20749, 22179, 24529, 25089, 25104, 25229, 25404, 27714, 27779, 29849, 30234, 32369, 33384, 34799 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Apparently there are no four subsequent numbers m with f(m) prime.

LINKS

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

MATHEMATICA

Reap[Do[If[PrimeQ[72*n^2+7]&&PrimeQ[72*(n+1)^2+7]&&PrimeQ[72*(n+2)^2+7], Sow[n]], {n, 0, 300000}]][[2, 1]]

Flatten[Position[Partition[Table[PrimeQ[72n^2+7], {n, 35000}], 3, 1], {True, True, True}]] (* Harvey P. Dale, Aug 17 2014 *)

CROSSREFS

Cf. A007522, A121068.

Sequence in context: A223372 A180334 A223290 * A050282 A096757 A101158

Adjacent sequences:  A121086 A121087 A121088 * A121090 A121091 A121092

KEYWORD

nonn

AUTHOR

Zak Seidov, Aug 11 2006

STATUS

approved

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Last modified November 19 20:42 EST 2019. Contains 329323 sequences. (Running on oeis4.)