A337759 Squares that are the sum of 3 distinct nonzero squares.

49, 81, 121, 169, 196, 225, 289, 324, 361, 441, 484, 529, 625, 676, 729, 784, 841, 900, 961, 1089, 1156, 1225, 1296, 1369, 1444, 1521, 1681, 1764, 1849, 1936, 2025, 2116, 2209, 2401, 2500, 2601, 2704, 2809, 2916, 3025, 3136, 3249, 3364, 3481, 3600, 3721, 3844, 3969

Offset

1,1

Comments

These are the squares in A004432. - Omar E. Pol, Sep 18 2020

Links

Table of n, a(n) for n=1..48.

Formula

a(n) = A161992(n)^2. - Andrew Howroyd, Sep 18 2020

Example

49 is a term because 6^2(36) + 3^2(9) + 2^2(4) = 7^2(49).
81 is a term because 8^2(64) + 4^2(16) + 1^2(1) = 9^2(81).
121 is a term because 9^2(81) + 6^2(36) + 2^2(4) = 11^2(121).
625 is a term because 9^2(81) + 12^2(144) + 20^2(400) = 25^2(625).

Mathematica

Select[Range[63]^2, Length @ Reduce[x^2 + y^2 + z^2 == # && 0 < x < y < z, {x, y, z}, Integers] > 0 &] (* Amiram Eldar, Sep 18 2020 *)

Crossrefs

Cf. A004432, A161992.

Sequence in context: A294028 A056938 A267986 * A207638 A286095 A106311

Adjacent sequences: A337756 A337757 A337758 * A337760 A337761 A337762

Keyword

nonn

Author

Joseph Caliendo, Sep 18 2020

Status

approved