A132777 Nonsquare numbers which are the sum of 2 distinct squares.

5, 10, 13, 17, 20, 26, 29, 34, 37, 40, 41, 45, 50, 52, 53, 58, 61, 65, 68, 73, 74, 80, 82, 85, 89, 90, 97, 101, 104, 106, 109, 113, 116, 117, 122, 125, 130, 136, 137, 145, 146, 148, 149, 153, 157, 160, 164

Offset: 1

Author

Rob Hubbard (hubbard.r(AT)gmail.com), Oct 08 2007

Keywords

• easy
• nonn

Comments

This is simply A001983 excluding the square numbers.

The squares of these numbers are also sums of two distinct nonzero squares. Including them gives A004431. - Jean-Christophe Hervé, Nov 11 2013

Examples

			5 = 4 + 1, and 5^2 = 16 + 9 ; 10 = 9 + 1, and 10^2 = 64 + 36. - _Jean-Christophe Hervé_, Nov 11 2013
		

Crossrefs

Cf. A001983, A004431.

Programs

Mathematica

selQ[n_] := !IntegerQ[Sqrt[n]] && Select[ PowersRepresentations[n, 2, 2], 0 <= #[[1]] < #[[2]]&] != {};
Select[Range[1000], selQ] (* Jean-François Alcover, Apr 20 2023 *)

Extensions

Definition corrected by Jean-Christophe Hervé, Nov 11 2013