A182834 Complement of A007590, except for initial zeros.

1, 3, 5, 6, 7, 9, 10, 11, 13, 14, 15, 16, 17, 19, 20, 21, 22, 23, 25, 26, 27, 28, 29, 30, 31, 33, 34, 35, 36, 37, 38, 39, 41, 42, 43, 44, 45, 46, 47, 48, 49, 51, 52, 53, 54, 55, 56, 57, 58, 59, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 85, 86, 87, 88, 89, 90, 91, 92

Offset: 1

Author

Clark Kimberling, Jan 07 2011

Keywords

• nonn
• easy

Comments

A245575(a(n)) mod 2 = 0, or, where even terms occur in A245575; a(A078633(n)) mod 2 = 0. - Reinhard Zumkeller, Aug 05 2014

Links

• Reinhard Zumkeller, Table of n, a(n) for n = 1..10000

Crossrefs

Cf. A007590.

Cf. A000196, A078633, A245575.

Programs

Haskell

a182834 n = a000196 (2 * n - 2) + n  -- Reinhard Zumkeller, Aug 05 2014

Mathematica

  a=2; b=-2;
  Table[n+Floor[(a*n+b)^(1/2)],{n,80}]
  Table[n-1+Ceiling[(n*n-b)/a],{n,50}]

Python

from math import isqrt
def A182834(n): return n+isqrt(n-1<<1) # Chai Wah Wu, Jul 28 2022

Formula

a(n) = n + floor(sqrt(2n-2)).