A022551 Numbers that are the sum of 2 squares and a nonnegative cube.

0, 1, 2, 3, 4, 5, 6, 8, 9, 10, 11, 12, 13, 14, 16, 17, 18, 19, 20, 21, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 56, 57, 58, 59, 60, 61, 62

Offset

1,3

Links

Jean-François Alcover, Table of n, a(n) for n = 1..943

Index entries for sequences related to sums of squares

Maple

isA022551 := proc(n)
    local a, b, c ;
    for c from 0 do
        if c^3 > n then
            return false;
        end if;
        for a from 0 do
            b2 := n-c^3-a^2 ;
            if b2 < a^2 then
                break;
            end if;
            if issqr(b2) then
                return true;
            end if;
        end do:
    end do:
end proc: # R. J. Mathar, Sep 02 2016

Mathematica

max = 1000;
Table[x^2 + y^2 + z^3, {x, 0, Sqrt[max]}, {y, x, Sqrt[max - x^2]}, {z, 0, (max - x^2 - y^2)^(1/3)}] // Flatten // Union // Select[#, # <= max&]& (* Jean-François Alcover, Mar 23 2020 *)

Crossrefs

Complement of A022552.

Sequence in context: A292638 A000378 A335513 * A172251 A286997 A187396

Adjacent sequences: A022548 A022549 A022550 * A022552 A022553 A022554

Keyword

nonn

Author

N. J. A. Sloane.

Status

approved