A083037 a(n)=2*A083036(n)-n. Also -A123737(n).

1, 0, -1, 0, 1, 0, 1, 2, 1, 0, 1, 0, -1, 0, 1, 0, -1, 0, -1, -2, -1, 0, -1, 0, 1, 0, -1, 0, 1, 0, 1, 2, 1, 0, 1, 0, -1, 0, 1, 0, 1, 2, 1, 0, 1, 2, 1, 2, 3, 2, 1, 2, 1, 0, 1, 2, 1, 0, 1, 0, -1, 0, 1, 0, 1, 2, 1, 0, 1, 0, -1, 0, 1, 0, -1, 0, -1, -2, -1, 0, -1, 0, 1, 0, -1, 0, 1, 0, 1, 2, 1, 0, 1, 0, -1, 0, 1, 0, -1, 0, -1, -2, -1, 0, -1, 0, 1, 0, -1, 0, -1, -2, -1, 0

Offset

1,8

Links

Table of n, a(n) for n=1..114.

Kevin O'Bryant, Bruce Reznick and Monika Serbinowska, Almost alternating sums, Amer. Math. Monthly, Vol. 113 (October 2006), pp. 673-688.

Formula

O'Bryant, Reznick, & Serbinowska show that |a(n)| <= k log n + 1, with k = 1/(2 log (1 + sqrt(2))), and further a(n) > k log n + 0.78 infinitely often. - Charles R Greathouse IV, Feb 07 2013

Prog

(PARI) a(n)=-sum(i=1, n, (-1)^sqrtint(2*i^2)) \\ Charles R Greathouse IV, Feb 07 2013

Crossrefs

Cf. A083035, A083036, A083038, A123737.

Sequence in context: A307198 A307196 A123737 * A247477 A072927 A307194

Adjacent sequences: A083034 A083035 A083036 * A083038 A083039 A083040

Keyword

sign

Author

Benoit Cloitre, Apr 17 2003

Status

approved