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

1,1

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

Links

Table of n, a(n) for n=1..60.

Example

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.

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

Crossrefs

Cf. A036275.

Sequence in context: A270590 A271378 A305837 * A346994 A070387 A331272

Adjacent sequences: A175552 A175553 A175554 * A175556 A175557 A175558

Keyword

nonn,base

Author

Michel Lagneau, Jun 29 2010

Status

approved