A214922 - OEIS

A214922

Numbers of the form x^2 + y^2 + z^3 + w^3 (x, y, z, w >= 0).

0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 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

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,3

COMMENTS

Conjecture: 23 is the only number not in this sequence.

Not the same as A004830: 239 is a term of this sequence but not of A004830. - R. J. Mathar and Joerg Arndt, Jul 28 2012

There are no other missing numbers from 24 to 10^8. - Giovanni Resta, Oct 12 2019

LINKS

Table of n, a(n) for n=1..54.

EXAMPLE

22 = 2^2 + 4^2 + 1^3 + 1^3, 22 is in this sequence.

CROSSREFS

Cf. A001481, A004999, A022549, A022550, A022551, A022552.

Sequence in context: A370133 A351576 A132264 * A004830 A081330 A359415

Adjacent sequences: A214919 A214920 A214921 * A214923 A214924 A214925

KEYWORD

nonn

AUTHOR

Philippe Deléham, Jul 20 2012

STATUS

approved