A027664 a(n)/10000000 gives sqrt(n) to 7 places.

10000000, 14142136, 17320508, 20000000, 22360680, 24494897, 26457513, 28284271, 30000000, 31622777, 33166248, 34641016, 36055513, 37416574, 38729833, 40000000, 41231056, 42426407, 43588989, 44721360, 45825757, 46904158, 47958315, 48989795, 50000000, 50990195

Offset: 1

Author

N. J. A. Sloane

Keywords

• nonn
• base

Programs

Maple

lprint(round(evalf(10000000*sqrt(n))));

Python

from math import isqrt
def A027664(n): return (m:=isqrt(k:=n*10**14))+int(k-m*(m+1)>=1) # Chai Wah Wu, Jul 31 2022