A274758 Least number whose square is the sum of two positive triangular numbers in exactly n ways.

2, 4, 9, 34, 91, 66, 534, 121, 134, 716, 40391, 516

Offset

1,1

Comments

a(13) > 4*10^7, if it exists. - Giovanni Resta, Jul 04 2016

Links

Table of n, a(n) for n=1..12.

Example

a(1) = 2 because 2^2 = 1 + 3.
a(2) = 4 because 4^2 = 1 + 15 = 6 + 10.
a(3) = 9 because 9^2 = 3 + 78 = 15 + 66 = 36 + 45.

Crossrefs

Cf. A000217, A000290, A052346.

Sequence in context: A053548 A054119 A259490 * A266929 A242986 A327057

Adjacent sequences: A274755 A274756 A274757 * A274759 A274760 A274761

Keyword

nonn,more

Author

Altug Alkan, Jul 04 2016

Extensions

a(9)-a(12) from Giovanni Resta, Jul 04 2016

Status

approved