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A287959
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Odd primes p such that p^2 divides A001205(p)-(p-1)/2.
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0
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OFFSET
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1,1
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COMMENTS
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Carlitz proved that A001205(p) == (p-1)/2 (mod p) for all odd primes p. This sequence consists of odd primes for which A001205(p) == (p-1)/2 (mod p^2) holds.
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LINKS
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MATHEMATICA
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a[1] = 0; a[2] = 0; a[3] = 1; a[n_] := a[n] = (n - 1)*(a[n - 1] + (n - 2)*a[n - 3]/2); lst = {}; k = 3; While[Length[lst] < 5, If[PrimeQ[k] && Divisible[a[k] - (k - 1)/2, k^2], lst = AppendTo[lst, k]]; k++]; lst
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CROSSREFS
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KEYWORD
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nonn,more
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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