perplexus.info :: Just Math : T times T creates another T??

T times T creates another T?? (Posted on 2015-01-11)

The squares of triangular numbers 1 and 6 are triangular numbers 1 and 36.

T1^2 = 1 * 1 = 1 = T1
T3^2 = 6 * 6 = 36 = T8

Are there additional triangular numbers whose squares form a triangular number?

Submitted by Ady TZIDON

Rating: 4.0000 (1 votes)

Solution: (Hide)

There is no other square triangular number beside 1 and 36 which is a square of a triangular number.
The source of proof:
L. J. Mordel, Diophantine Equations, 1969, Academic Press, London, Theorem 7, pp. 268-269).

Comments: ( You must be logged in to post comments.)

Subject	Author	Date
Forgetting zero	Ady TZIDON	2015-01-13 19:48:18
Another thought	broll	2015-01-12 22:37:21
No solution, maybe just an interesting byway	xdog	2015-01-12 15:17:01
An equivalent problem	broll	2015-01-12 12:51:54
re(3): Solution	Steve Herman	2015-01-12 12:13:30
re(2): Solution	Harry	2015-01-12 11:09:08
re: Solution	Steve Herman	2015-01-12 08:26:04
Solution	Harry	2015-01-11 11:53:37

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