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A213189 Triangular numbers which are leg of a Pythagorean triple with hypotenuse in A213188. 1
6, 36, 91, 120, 210, 253, 300, 378, 528, 630, 1176, 2016, 2346, 3003, 3240, 3828, 4560, 4656, 4950, 5460, 6105, 6903, 7140, 7260, 8778, 10296, 11628, 13530, 14028, 14196, 15400, 17766, 19110, 23220, 23436, 24310, 25200, 26796, 32640, 34980, 41616, 43365, 44253, 52326, 55278 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..45.

EXAMPLE

Triangular 91 and triangular 325 form a Pythagorean triple {325, 91, 312}.

PROG

(PARI) {for(i=1, 10^3, k=i+1; v=1; a=i*(i+1)/2; while(k<i*i&&v, b=k*(k+1)/2; if(issquare(b*b-a*a), v=0; print1(a, ", ")); k+=1))}

CROSSREFS

Cf. A213188.

Sequence in context: A207026 A207171 A207454 * A080857 A108158 A207559

Adjacent sequences:  A213186 A213187 A213188 * A213190 A213191 A213192

KEYWORD

nonn

AUTHOR

Antonio Roldán, Feb 28 2013

STATUS

approved

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Last modified December 14 19:27 EST 2019. Contains 329987 sequences. (Running on oeis4.)