

A218486


Positive numbers differing from next 2 greater squares by squares.


4



48, 96, 160, 240, 288, 336, 448, 480, 576, 720, 960, 1008, 1344, 1440, 1728, 2016, 2160, 2400, 2640, 2688, 3168, 3360, 3456, 3744, 4320, 4368, 4480, 5040, 5280, 5760, 6336, 6720, 7200, 7488, 8640, 8736, 8800, 9408, 10080, 10560, 10800, 11520, 12096, 12480
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OFFSET

1,1


COMMENTS

All terms are even. The sequence is infinite. E.g., positive terms of A173121 {48, 288, 960, 2400, 5040, 9408, 16128, 25920, 39600,...} is infinite subsequence of A218486.  Zak Seidov, Nov 26 2013
Another infinite subsequence is {96, 480, 1440, 3360, 6720, 12096, 20160, ...} = 96 *binomial(m,4) = 96*(positive terms in A000332).  Zak Seidov, Nov 26 2013


LINKS

Zak Seidov, Table of n, a(n) for n = 1..1000
E. J. Barbeau, Numbers differing from consecutive squares by squares, Canad. Math. Bull. 28(1985), pp. 337342.


EXAMPLE

48 = 7^2  1^2 = 8^2  4^2.


PROG

(PARI) sq2(n) = {for (i=1, n, a = sqrtint(i) + 1; if (issquare(a^2i) && issquare((a+1)^2i), print1(i, ", ")); ); }


CROSSREFS

Cf. A173121, A218485, A218487, A218488.
Sequence in context: A260063 A211723 A274899 * A043418 A031486 A044186
Adjacent sequences: A218483 A218484 A218485 * A218487 A218488 A218489


KEYWORD

nonn


AUTHOR

Michel Marcus, Oct 30 2012


STATUS

approved



