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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 (list; graph; refs; listen; history; text; internal format)
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

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Last modified December 5 18:48 EST 2021. Contains 349557 sequences. (Running on oeis4.)