A175555 Preperiodic part of the decimal expansion of 1/k as k runs through A065502.

5, 25, 2, 1, 125, 1, 8, 0, 0, 625, 0, 5, 0, 41, 4, 0, 3, 0, 3125, 0, 0, 2, 0, 25, 0, 2, 0, 0, 208, 2, 1, 0, 0, 17, 0, 1, 0, 15625, 0, 0, 1, 0, 13, 0, 1, 1, 0, 125, 0, 1, 0, 0, 11, 0, 1, 0, 0, 1041, 0, 1

Offset: 1

Author

Michel Lagneau, Jun 29 2010

Keywords

• nonn
• base

Comments

Multiples of 2 or 5 generate a quotient with a preperiodic sequence of digits, for example 1/24 = 0.041666666..., and 41 is the decimal form of the preperiodic part.

Usually a(n) = A114205(A065502(n)), but the convention in A114205 that leading zeros in the periodic part are attached to the preperiodic part seems not to be used here. - R. J. Mathar, Jul 20 2012

Examples

			a(14)=4 is in the sequence because 1/25 = 0.040000... and 4 is the prefix.
208 is in the sequence because 1/48 = 2083333.... and 208 is the prefix.
		

Crossrefs

Cf. A036275.

Programs

Maple

A175555 := proc(n)
        local k,s,al ;
        k := A065502(n) ;
        for s from 1 do
                for al from 0 to s-1 do
                        if (10^s-10^al) mod k = 0 then
                                return floor(10^al/k) ;
                        end if;
                end do:
        end do:
end proc: # R. J. Mathar, Jul 22 2012