A145951 a(n) = floor(d*Pi*n) where d is the initial digit of the fractional part of Pi*n.

3, 12, 37, 62, 109, 150, 197, 25, 56, 125, 172, 226, 326, 395, 47, 100, 213, 282, 358, 502, 593, 69, 144, 226, 392, 490, 678, 791, 91, 188, 292, 502, 622, 854, 989, 0, 232, 358, 612, 753, 1030, 1187, 0, 276, 424, 722, 885, 1055, 1385

Offset: 1

Author

Matthew Jorgensen (matthew.a.jorgensen(AT)gmail.com), Oct 25 2008

Keywords

• base
• easy
• nonn

Examples

			For n=5, 5*Pi = 15.707...; take the 7 from 15.(7)07... and multiply again: 7*5*Pi = 109.955... => 109.
		

Links

• Robert Israel, Table of n, a(n) for n = 1..10000

Crossrefs

Cf. A094562.

Programs

Maple

f:= proc(n) local d;
   d:= floor(10*n*Pi) mod 10;
   floor(d*n*Pi)
end proc:
seq(f(n),n=1..1000); # Robert Israel, Dec 25 2015

Formula

a(n) = floor(A094562(n)*Pi*n).