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A072522 Smallest number a(n)>a(n-1) such that T(a(n-1))+T(a(n))=T(m) for some m, a(1)=3; T(i) are the triangular numbers. 4
3, 5, 6, 9, 13, 44, 58, 854, 896, 1194, 1253, 1469, 1628, 2170, 2403, 3205, 3366, 3395, 4370, 4454, 4676, 6234, 6545, 6873, 9165, 9624, 12833, 17110, 17450, 18524, 24012, 25025, 25652, 28242, 37657, 356750, 400894, 420938, 561250, 1347002 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Chai Wah Wu, Table of n, a(n) for n = 1..2401

PROG

(PARI) p=3; print1("3, "); for(n=2, 50, t=p*(p+1)/2; for(k=p, 10^9, u=t+k*(k+1)/2; v=floor(sqrt(2*u)); if(v*(v+1)/2==u, print1(k", "); p=k; break)))

CROSSREFS

Cf. A072521, A082183. Values of m are in A080824.

Sequence in context: A039873 A096394 A075472 * A294909 A070111 A070117

Adjacent sequences:  A072519 A072520 A072521 * A072523 A072524 A072525

KEYWORD

nonn

AUTHOR

Amarnath Murthy, Jul 31 2002

EXTENSIONS

Edited by Ralf Stephan, Mar 27 2003

STATUS

approved

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Last modified August 9 18:32 EDT 2020. Contains 336326 sequences. (Running on oeis4.)