A277551 Numbers k such that k/5^m == 2 (mod 5), where 5^m is the greatest power of 5 that divides k.

2, 7, 10, 12, 17, 22, 27, 32, 35, 37, 42, 47, 50, 52, 57, 60, 62, 67, 72, 77, 82, 85, 87, 92, 97, 102, 107, 110, 112, 117, 122, 127, 132, 135, 137, 142, 147, 152, 157, 160, 162, 167, 172, 175, 177, 182, 185, 187, 192, 197, 202, 207, 210, 212, 217, 222, 227

Offset

1,1

Comments

Positions of 2 in A277543. Numbers that have 2 as their rightmost nonzero digit when written in base 5.

This is one sequence in a 4-way splitting of the positive integers; the other three are indicated in the Mathematica program.

Links

Clark Kimberling, Table of n, a(n) for n = 1..10000

Mathematica

z = 200; a[b_] := Table[Mod[n/b^IntegerExponent[n, b], b], {n, 1, z}]
p[b_, d_] := Flatten[Position[a[b], d]]
p[5, 1] (* A277550 *)
p[5, 2] (* A277551 *)
p[5, 3] (* A277555 *)
p[5, 4] (* A277548 *)

Prog

(PARI) isok(n) = n/5^valuation(n, 5) % 5 == 2; \\ Michel Marcus, Oct 21 2016

Crossrefs

Cf. A277543, A277550, A277555, A277548.

Sequence in context: A134712 A030344 A190433 * A029904 A026364 A203621

Adjacent sequences: A277548 A277549 A277550 * A277552 A277553 A277554

Keyword

nonn,easy

Author

Clark Kimberling, Oct 20 2016

Status

approved