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A271676
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Prime powers k such that 3k + 4 is a perfect square.
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1
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OFFSET
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1,1
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COMMENTS
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This sequence is complete. For proof see the link. - Altug Alkan, Apr 15 2016
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LINKS
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EXAMPLE
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4 is in this sequence because 3*4 + 4 = 16 = 4^2,
7 is in this sequence because 3*7 + 4 = 25 = 5^2,
32 is in this sequence because 3*32 + 4 = 100 = 10^2,
64 is in this sequence because 3*64 + 4 = 196 = 14^2.
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MATHEMATICA
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Select[Range[10^4], PrimePowerQ@ # && IntegerQ@ Sqrt[3 # + 4] &] (* Michael De Vlieger, Apr 12 2016 *)
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PROG
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(Magma) [n: n in [2..10000000] | IsPrimePower(n) and IsSquare(3*n + 4)];
(PARI) lista(nn) = for(n=1, nn, if(isprimepower(n) && issquare(3*n+4), print1(n, ", "))); \\ Altug Alkan, Apr 12 2016
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CROSSREFS
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KEYWORD
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nonn,fini,full
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AUTHOR
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STATUS
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approved
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