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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 (list; graph; refs; listen; history; text; internal format)
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. 337-342.

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^2-i) && issquare((a+1)^2-i), 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

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Last modified December 7 22:50 EST 2021. Contains 349590 sequences. (Running on oeis4.)