A071413 a(n) = if n=0 then 0 else a(floor(n/2))+n*(-1)^(n mod 2).

0, -1, 1, -4, 5, -4, 2, -11, 13, -4, 6, -15, 14, -11, 3, -26, 29, -4, 14, -23, 26, -15, 7, -38, 38, -11, 15, -38, 31, -26, 4, -57, 61, -4, 30, -39, 50, -23, 15, -62, 66, -15, 27, -58, 51, -38, 8, -85, 86, -11, 39, -62, 67, -38, 16, -93, 87, -26, 32, -85, 64, -57, 5

Offset

0,4

Links

Reinhard Zumkeller, Table of n, a(n) for n = 0..10000

Ralf Stephan, Some divide-and-conquer sequences with (relatively) simple ordinary generating functions.

Ralf Stephan, Table of generating functions

Prog

(Haskell)
a071413 0 = 0
a071413 n | m == 0    = a071413 n' + n
          | otherwise = a071413 n' - n  where (n', m) = divMod n 2
-- Reinhard Zumkeller, Jun 01 2013

Crossrefs

Cf. A005187.

Sequence in context: A011427 A366610 A175622 * A161811 A016717 A366153

Adjacent sequences: A071410 A071411 A071412 * A071414 A071415 A071416

Keyword

sign

Author

Reinhard Zumkeller, Jun 24 2000

Status

approved