A026496 a(n) = least positive integer > a(n-1) and not a(i)^2 + a(j)^2 + a(k)^2 for 1<=i<=j<=k<=n.

1, 2, 4, 5, 7, 8, 10, 11, 13, 14, 15, 16, 17, 19, 20, 22, 23, 25, 26, 28, 29, 31, 32, 34, 35, 37, 38, 39, 40, 41, 43, 44, 46, 47, 49, 50, 52, 53, 55, 56, 58, 59, 60, 61, 62, 63, 64, 65, 67, 68, 70, 71, 73, 74, 76, 77, 79, 80, 82, 83, 85, 86, 87, 88, 89, 91, 92, 94, 95, 97, 98, 100

Offset

1,2

Links

Table of n, a(n) for n=1..72.

Mathematica

FixedPoint[Complement[Range@100, Flatten@Outer[Plus, #^2, #^2, #^2]] &, {}] (* Ivan Neretin, Feb 15 2016 *)

Crossrefs

Sequence in context: A307513 A186515 A078934 * A056127 A186352 A186157

Adjacent sequences: A026493 A026494 A026495 * A026497 A026498 A026499

Keyword

nonn

Author

Clark Kimberling

Extensions

Corrected, more terms added by Ivan Neretin, Feb 16 2016

Status

approved