A274090 a(n) = nearest integer to n^2 * cos(sqrt(n)).

0, 1, 1, -1, -7, -15, -28, -43, -61, -80, -100, -119, -137, -151, -162, -167, -167, -161, -147, -125, -95, -57, -11, 44, 107, 177, 255, 339, 429, 524, 623, 725, 830, 935, 1040, 1143, 1244, 1342, 1434, 1520, 1599, 1669, 1730, 1780, 1819, 1845, 1858, 1857, 1841, 1810, 1763, 1700, 1621, 1525

Offset: 0

Author

N. J. A. Sloane, Jun 10 2016

Keywords

• sign

Links

• N. J. A. Sloane and Chai Wah Wu, Table of n, a(n) for n = 0..10000 n = 0..1000 from N. J. A. Sloane.

Crossrefs

Sequences of the same type: A272695, A274086, A274087, A274088, A274090, A274091, A274092, A274095, A274096, A274097, A274101, A274102.

Programs

Maple

Digits:=50: f:=n->round(evalf(n^2*cos(sqrt(n)))); [seq(f(n),n=0..120)];

Python

from sympy import cos, sqrt
def A274090(n):
    return int((n**2*cos(sqrt(n))).round()) # Chai Wah Wu, Jun 11 2016