A348596 a(n) = A068527(2*n+1).

0, 1, 4, 2, 0, 5, 3, 1, 8, 6, 4, 2, 0, 9, 7, 5, 3, 1, 12, 10, 8, 6, 4, 2, 0, 13, 11, 9, 7, 5, 3, 1, 16, 14, 12, 10, 8, 6, 4, 2, 0, 17, 15, 13, 11, 9, 7, 5, 3, 1, 20, 18, 16, 14, 12, 10, 8, 6, 4, 2, 0, 21, 19, 17, 15, 13, 11, 9, 7, 5, 3, 1, 24, 22, 20, 18, 16

Offset: 0

Author

Ryan Jean, Feb 22 2022

Keywords

• nonn
• easy

Crossrefs

Cf. A068527, A046092 (position of 0's), A056220 (position of 1's), A350962.

Programs

Python

from math import isqrt
def A348596(n): return (isqrt(2*n)+1)**2-2*n-1 # Chai Wah Wu, Feb 22 2022

Formula

a(n) = (ceiling(sqrt(2*n + 1)))^2 - (2*n + 1).

Extensions

Edited by N. J. A. Sloane, Feb 22 2022