

A277551


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


5



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
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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 4way splitting of the positive integers; the other three are indicated in the Mathematica program.


LINKS



MATHEMATICA

z = 200; a[b_] := Table[Mod[n/b^IntegerExponent[n, b], b], {n, 1, z}]
p[b_, d_] := Flatten[Position[a[b], d]]


PROG

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


CROSSREFS



KEYWORD

nonn,easy


AUTHOR



STATUS

approved



