A274094 a(0)=0; thereafter (-1)^(n+1)*n appears n times.

0, 1, -2, -2, 3, 3, 3, -4, -4, -4, -4, 5, 5, 5, 5, 5, -6, -6, -6, -6, -6, -6, 7, 7, 7, 7, 7, 7, 7, -8, -8, -8, -8, -8, -8, -8, -8, 9, 9, 9, 9, 9, 9, 9, 9, 9, -10, -10, -10, -10, -10, -10, -10, -10, -10, -10, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, -12, -12, -12, -12, -12, -12, -12, -12, -12, -12

Offset

0,3

Links

Chai Wah Wu, Table of n, a(n) for n = 0..10011

Maple

s1:=[0];
for n from 1 to 15 do
for i from 1 to n do
s1:=[op(s1), (-1)^(n+1)*n]; od: od:
s1;

Prog

(Python)
A274094_list = [0]+ [i for n in range(1, 142) for i in [n if n % 2 else -n]*n] # Chai Wah Wu, Jun 11 2016

Crossrefs

Cf. A002024, A274093.

Partial sums of A010816.

Sequence in context: A033810 A253272 A023965 * A274093 A087847 A107436

Adjacent sequences: A274091 A274092 A274093 * A274095 A274096 A274097

Keyword

sign

Author

N. J. A. Sloane, Jun 10 2016

Status

approved