A046039 Numbers which cannot be represented as a sum of distinct 4th powers.

2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74

Offset

1,1

Comments

Last term is a(889576) = 5134240. [Charles R Greathouse IV, Feb 26 2012]

Links

Vaclav Kotesovec, Table of n, a(n) for n = 1..60000

Eric Weisstein's World of Mathematics, Biquadratic Number

Mathematica

max = 2000; f[x_] := Product[1 + x^(k^4), {k, 1, 10}]; A003999 = Exponent[#, x]& /@ List @@ Normal[Series[f[x], {x, 0, max}]] // Rest; A046039 = Complement[Range[max], A003999][[1 ;; 71]](* Jean-François Alcover, Nov 09 2012, after Charles R Greathouse IV *)

Prog

(PARI) select( is_A046039(n, m=n)={m^4>n&& m=sqrtnint(n, 4); n!=m^4&& !while(m>1, is_A046039(n-m^4, m--)||return)}, [1..74]) \\ M. F. Hasler, Apr 21 2020

Crossrefs

Cf. A001422, A001476. Complement of A003999.

Cf. A279487.

Sequence in context: A331026 A098312 A279487 * A023784 A028823 A258264

Adjacent sequences: A046036 A046037 A046038 * A046040 A046041 A046042

Keyword

nonn,fini

Author

Eric W. Weisstein

Status

approved