A086340 Numbers n such that 1 + (n-1)*n*(n+1) is a square.

1, 3, 5, 56

Offset

1,2

References

M. Lambrou, Solution to problem 2411, Crux Mathematicorum, Feb. 2000 26(1) 59-60 CMS.

Links

Table of n, a(n) for n=1..4.

Prog

(PARI) isok(n) = issquare(1 + (n-1)*n*(n+1)) \\ Michel Marcus, Jul 27 2013

Crossrefs

Sequence in context: A260225 A020462 A087602 * A248923 A155121 A106914

Adjacent sequences: A086337 A086338 A086339 * A086341 A086342 A086343

Keyword

fini,nonn

Author

Lekraj Beedassy, Sep 02 2003

Status

approved