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A212842 Numbers expressible as sum of squares of two distinct positive triangular numbers exactly in two ways. 1
47125, 279225, 354061, 549181, 672409, 1626409, 3349125, 5504500, 6186250, 29811609, 32035636, 36082909, 66280609, 178651252, 265364325, 379845684, 380287441, 380367010, 385371234, 420373045, 526535109, 622542601, 654992101, 1065369601, 1298353716, 1339962850 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Are there numbers expressible as T(m)^2 + T(n)^2 in exactly 3 (and more?) ways?

LINKS

Zak Seidov, Table of n, a(n) for n = 1..130

EXAMPLE

47125 = T(14)^2 + T(19)^2 = 105^2 + 190^2, and

47125 = T(10)^2 + T(20)^2 = 55^2 + 210^2.

CROSSREFS

Inspired by A212795.

Sequence in context: A250688 A183601 A206252 * A254549 A254556 A254479

Adjacent sequences:  A212839 A212840 A212841 * A212843 A212844 A212845

KEYWORD

nonn

AUTHOR

Zak Seidov, May 28 2012

STATUS

approved

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Last modified January 28 23:12 EST 2022. Contains 350670 sequences. (Running on oeis4.)