A340507 a(n) = floor(sqrt(2*n)) - A003056(n).

0, 0, 1, 0, 0, 1, 0, 0, 1, 1, 0, 0, 0, 1, 1, 0, 0, 0, 1, 1, 1, 0, 0, 0, 0, 1, 1, 1, 0, 0, 0, 0, 1, 1, 1, 1, 0, 0, 0, 0, 0, 1, 1, 1, 1, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0

Offset

0

Comments

This is A172471 - A003056.

Conjecture: This is an unsigned version of A072785.

Links

Alois P. Heinz, Table of n, a(n) for n = 0..20000

Prog

(PARI) a(n) = sqrtint(2*n) - (sqrtint(8*n+1)-1)\2; \\ Michel Marcus, Jan 25 2021
(Python)
from math import isqrt
def A340507(n): return isqrt(m:=n<<1)-(isqrt((m<<2)+1)-1>>1) # Chai Wah Wu, Aug 09 2022

Crossrefs

Cf. A003056, A072785, A172471.

Sequence in context: A288520 A285177 A144595 * A072785 A188297 A289128

Adjacent sequences: A340504 A340505 A340506 * A340508 A340509 A340510

Keyword

nonn

Author

N. J. A. Sloane, Jan 25 2021

Status

approved