A249040 Number of even terms in first n terms of A249039.

0, 1, 2, 2, 2, 2, 3, 3, 4, 5, 6, 7, 7, 8, 9, 9, 9, 10, 10, 10, 10, 10, 10, 11, 11, 11, 11, 12, 12, 13, 14, 14, 14, 15, 15, 16, 17, 18, 18, 19, 20, 21, 22, 23, 24, 24, 25, 26, 27, 28, 28, 29, 30, 30, 30, 31, 31, 32, 33, 34, 34, 35, 36, 36, 36, 37, 37, 37, 37, 38, 38, 39, 40, 40, 40, 41, 41

Offset: 1

Author

N. J. A. Sloane, Oct 26 2014

Keywords

• nonn

Links

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

Crossrefs

Cf. A249039, A249041.

Programs

Haskell

a249040 n = a249040_list !! (n-1)
a249040_list = tail $ scanl (\i j -> i + 1 - mod j 2) 0 a249039_list
-- Reinhard Zumkeller, Nov 11 2014

Maple

See A249039.

Formula

For n > 1: a(n) = a(n-1) + 1 - A249039(n) mod 2. - Reinhard Zumkeller, Nov 11 2014