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A307492
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Numbers that are both centered square and square pyramidal.
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1
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OFFSET
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1,2
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COMMENTS
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If it exists, a(5) > 10^29. - Bert Dobbelaere, Apr 12 2019
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LINKS
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Table of n, a(n) for n=1..4.
Eric Weisstein's World of Mathematics, Centered Square Number
Eric Weisstein's World of Mathematics, Square Pyramidal Number
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MATHEMATICA
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csQ[n_] := IntegerQ[Sqrt[2*n-1]]; Select[Table[n(n+1)(2n+1)/6, {n, 0, 1000}], csQ] (* Amiram Eldar, Apr 11 2019 *)
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CROSSREFS
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Intersection of A000330 and A001844.
Cf. A008844, A039596, A131750, A307491.
Sequence in context: A193366 A228547 A193148 * A165711 A167369 A259161
Adjacent sequences: A307489 A307490 A307491 * A307493 A307494 A307495
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KEYWORD
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nonn,more
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AUTHOR
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Ilya Gutkovskiy, Apr 10 2019
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STATUS
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approved
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