A075434 Numbers that are not the sum of two perfect powers.

1, 3, 4, 6, 7, 11, 14, 15, 19, 21, 22, 23, 27, 30, 38, 39, 42, 46, 47, 49, 51, 55, 56, 60, 62, 66, 67, 69, 70, 71, 75, 77, 78, 79, 83, 84, 86, 87, 88, 92, 93, 94, 95, 99, 102, 103, 105, 107, 110, 111, 112, 114, 115, 118, 119, 120, 121, 123, 124, 131, 135, 138, 139, 140

Offset: 1

Author

Zak Seidov, Oct 11 2002

Keywords

• easy
• nonn

Crossrefs

Cf. A001597, complement of A070049.

Programs

PARI

lista(nn) = {vec = vector(nn, i, i); pp = concat(1, select(i->ispower(i) , vec)); sumpp = Set(); for (i = 1, #pp, for (j = 1, #pp, sumpp = Set(concat(sumpp, pp[i]+pp[j])););); for (i = 1, nn, if (! setsearch(sumpp, i), print1(i, ", ")););} \\ Michel Marcus, Oct 04 2013