A027923 a(n) = least k such that E{1,2,...,k} >= 1^2 + 2^2 + ... + n^2, where E = 2nd elementary symmetric function.

1, 2, 3, 3, 4, 5, 5, 6, 6, 7, 7, 8, 8, 9, 9, 10, 10, 11, 11, 12, 12, 13, 13, 13, 14, 14, 15, 15, 16, 16, 16, 17, 17, 18, 18, 18, 19, 19, 19, 20, 20, 21, 21, 21, 22, 22, 22, 23, 23, 24, 24, 24, 25, 25, 25, 26, 26, 26, 27, 27, 27, 28, 28, 28, 29

Offset

1,2

Links

Table of n, a(n) for n=1..65.

Formula

min{k: A000914(k) >= A000330(n)}. - R. J. Mathar, Oct 31 2011

Crossrefs

Sequence in context: A119466 A100922 A047785 * A167743 A020888 A196393

Adjacent sequences: A027920 A027921 A027922 * A027924 A027925 A027926

Keyword

nonn

Author

Clark Kimberling

Status

approved