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A274102
a(n) = nearest integer to k*sin(sqrt(k)+j*Pi) where n = 2*k+j, j=0 or 1.
12
0, 0, 1, -1, 2, -2, 3, -3, 4, -4, 4, -4, 4, -4, 3, -3, 2, -2, 1, -1, 0, 0, -2, 2, -4, 4, -6, 6, -8, 8, -10, 10, -12, 12, -14, 14, -16, 16, -18, 18, -19, 19, -21, 21, -22, 22, -23, 23, -24, 24, -24, 24, -24, 24, -24, 24, -23, 23, -23, 23, -22, 22, -20, 20, -19, 19, -17, 17, -15, 15, -13, 13, -10, 10, -7
OFFSET
0,5
LINKS
FORMULA
a(2n) = A274095(n), a(2n+1) = -A274095(n). - Chai Wah Wu, Jun 11 2016
MAPLE
Digits:=50:
ft:=proc(n, t) local k, j;
j:=(n mod t); k:=(n-j)/t;
round(evalf(k*sin(sqrt(k)+j*Pi)));
end;
[seq(ft(n, 2), n=0..120)];
CROSSREFS
KEYWORD
sign
AUTHOR
N. J. A. Sloane, Jun 11 2016
EXTENSIONS
Definition corrected by N. J. A. Sloane, Jun 20 2016
STATUS
approved