A184004 a(n) = n + floor(sqrt(4n/3)); complement of A184005.

2, 3, 5, 6, 7, 8, 10, 11, 12, 13, 14, 16, 17, 18, 19, 20, 21, 22, 24, 25, 26, 27, 28, 29, 30, 31, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 85, 86, 87, 88, 89, 90

Offset

1,1

Links

G. C. Greubel, Table of n, a(n) for n = 1..5000

Mathematica

a=4/3; b=0;
Table[n+Floor[(a*n+b)^(1/2)], {n, 80}]
Table[n-1+Ceiling[(n*n-b)/a], {n, 60}]

Prog

(PARI) for(n=1, 100, print1(n + floor(sqrt(4*n/3)), ", ")) \\ G. C. Greubel, Jul 22 2017
(PARI) a(n) = n + sqrtint(4*n/3); \\ Michel Marcus, Oct 01 2024
(Python)
from math import isqrt
def A184004(n): return n+isqrt((n<<2)//3) # Chai Wah Wu, Oct 01 2024

Crossrefs

Cf. A184005.

Sequence in context: A028962 A028968 A029598 * A183292 A039193 A028798

Adjacent sequences: A184001 A184002 A184003 * A184005 A184006 A184007

Keyword

nonn,easy

Author

Clark Kimberling, Jan 08 2011

Status

approved