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A144975
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Centered heptagonal twin prime numbers.
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1
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43, 71, 197, 463, 1933, 5741, 8233, 9283, 11173, 14561, 34651, 41203, 57793, 68111, 84631, 104147, 139301, 168631, 207523, 244861, 307693, 333103, 357281, 415381, 465011, 475273, 506731, 592663, 595547, 607153, 729373, 742211, 781397, 876751
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OFFSET
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1,1
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LINKS
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EXAMPLE
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43 is a term since it is centered heptagonal and the greater member of the twin primes pair (41, 43).
71 is a term since it is centered heptagonal and the lesser member of the twin primes pair (71, 73).
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MATHEMATICA
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TwinPrimeQ[n_]:=If[PrimeQ[n], If[PrimeQ[n-2]||PrimeQ[n+2], True, False], False](*TwinPrimeQ*) lst={}; Do[p=(7*n^2-7*n+2)/2; If[TwinPrimeQ[p], AppendTo[lst, p]], {n, 2*6!}]; lst
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PROG
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(Magma) [a:k in [1..510]|IsPrime(a) and (IsPrime(a-2) or IsPrime(a+2)) where a is (7*k^2-7*k+2) div 2]; // Marius A. Burtea, Jan 30 2020
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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