

A307492


Numbers that are both centered square and square pyramidal.


1




OFFSET

1,2


COMMENTS

If it exists, a(5) > 10^29.  Bert Dobbelaere, Apr 12 2019


LINKS

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


MATHEMATICA

csQ[n_] := IntegerQ[Sqrt[2*n1]]; Select[Table[n(n+1)(2n+1)/6, {n, 0, 1000}], csQ] (* Amiram Eldar, Apr 11 2019 *)


CROSSREFS

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


KEYWORD

nonn,more


AUTHOR

Ilya Gutkovskiy, Apr 10 2019


STATUS

approved



