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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
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
Sequence in context: A223372 A180334 A223290 * A362697 A050282 A096757
KEYWORD
nonn
AUTHOR
Zak Seidov, Aug 11 2006
STATUS
approved

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Last modified April 24 00:30 EDT 2024. Contains 371917 sequences. (Running on oeis4.)