A184110 n + floor(3*sqrt(n+1)).

5, 7, 9, 10, 12, 13, 15, 17, 18, 19, 21, 22, 24, 25, 27, 28, 29, 31, 32, 33, 35, 36, 37, 39, 40, 41, 42, 44, 45, 46, 47, 49, 50, 51, 53, 54, 55, 56, 57, 59, 60, 61, 62, 64, 65, 66, 67, 69, 70, 71, 72, 73, 75, 76, 77, 78, 79, 81, 82, 83, 84, 85, 87, 88, 89, 90, 91, 92, 94, 95, 96, 97, 98, 99, 101, 102, 103, 104, 105, 107, 108, 109, 110, 111, 112, 113, 115, 116, 117, 118, 119, 120, 122, 123, 124, 125, 126, 127, 129, 130

Offset

1,1

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}]
#+Floor[3*Sqrt[#+1]]&/@Range[150] (* Harvey P. Dale, Jul 11 2014 *)

Crossrefs

Cf. A184016, A184108.

Sequence in context: A129270 A153031 A334303 * A138892 A190202 A005523

Adjacent sequences: A184107 A184108 A184109 * A184111 A184112 A184113

Keyword

nonn,easy

Author

Clark Kimberling, Jan 09 2011

Status

approved