A184108 n + floor(3*sqrt(n-1)); complement of A184109.

1, 5, 7, 9, 11, 12, 14, 15, 17, 19, 20, 21, 23, 24, 26, 27, 29, 30, 31, 33, 34, 35, 37, 38, 39, 41, 42, 43, 44, 46, 47, 48, 49, 51, 52, 53, 55, 56, 57, 58, 59, 61, 62, 63, 64, 66, 67, 68, 69, 71, 72, 73, 74, 75, 77, 78, 79, 80, 81, 83, 84, 85, 86, 87, 89, 90, 91, 92, 93, 94, 96, 97, 98, 99, 100, 101, 103, 104, 105, 106, 107, 109, 110, 111, 112, 113, 114, 115, 117, 118, 119, 120, 121, 122, 124, 125, 126, 127, 128, 129

Offset

1,2

Links

Table of n, a(n) for n=1..100.

Formula

a(n) = n + floor(3*sqrt(n-1))

Mathematica

a=9; b=-9;
Table[n+Floor[(a*n+b)^(1/2)], {n, 100}]
Table[n-1+Ceiling[(n*n-b)/a], {n, 90}]

Crossrefs

Cf. A184109.

Sequence in context: A165513 A002342 A080353 * A254760 A279289 A175382

Adjacent sequences: A184105 A184106 A184107 * A184109 A184110 A184111

Keyword

nonn,easy

Author

Clark Kimberling, Jan 09 2011

Status

approved