A293175 Integers with precisely six partitions into sums of four squares of nonnegative numbers.

66, 81, 97, 99, 105, 110, 115, 121, 123, 124, 137, 139, 141, 149, 155, 156, 158, 159, 164, 179, 188, 239, 264, 284, 440, 496, 624, 632, 656, 752, 1056, 1136, 1760, 1984, 2496, 2528, 2624, 3008, 4224, 4544, 7040, 7936, 9984, 10112, 10496, 12032, 16896, 18176

Offset: 1

Author

Robert Price, Oct 27 2017

Keywords

• nonn

Comments

A002635(a(n)) = 6.

Links

• D. H. Lehmer, On the Partition of Numbers into Squares, The American Mathematical Monthly, Vol. 55, No. 8, October 1948, pp. 476-481.
• Index entries for sequences related to sums of squares

Crossrefs

Cf. A001156, A002635, A006431, A025428, A180149, A245022, A294282, A294297.

Programs

Mathematica

f[n_] := Length@ PowersRepresentations[n, 4, 2]; Select[ Range@ 19000, f@# == 6 &] (* Robert G. Wilson v, Oct 27 2017 *)