A277543 - OEIS

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A277543

a(n) = n/5^m mod 5, where 5^m is the greatest power of 5 that divides n.

6

1, 2, 3, 4, 1, 1, 2, 3, 4, 2, 1, 2, 3, 4, 3, 1, 2, 3, 4, 4, 1, 2, 3, 4, 1, 1, 2, 3, 4, 1, 1, 2, 3, 4, 2, 1, 2, 3, 4, 3, 1, 2, 3, 4, 4, 1, 2, 3, 4, 2, 1, 2, 3, 4, 1, 1, 2, 3, 4, 2, 1, 2, 3, 4, 3, 1, 2, 3, 4, 4, 1, 2, 3, 4, 3, 1, 2, 3, 4, 1, 1, 2, 3, 4, 2, 1

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

OFFSET

1,2

COMMENTS

a(n) is the rightmost nonzero digit in the base 5 expansion of n (A007091).

LINKS

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

FORMULA

a(n) = A132739(n) mod 5 = A010874(A132739(n)). - Michel Marcus, Oct 20 2016

EXAMPLE

a(20) = (20/5 mod 5) = 4.

MATHEMATICA

Table[Mod[n/5^IntegerExponent[n, 5], 5], {n, 1, 160}]

PROG

(PARI) a(n) = n/5^valuation(n, 5) % 5; \\ Michel Marcus, Oct 20 2016

CROSSREFS

Cf. A007091, A010874, A132739.

Cf. A277550, A277551, A277555, A277548 (positions of 1, 2, 3 and 4 in this sequence).

Sequence in context: A138297 A374724 A139458 * A190594 A338803 A104412

Adjacent sequences: A277540 A277541 A277542 * A277544 A277545 A277546

KEYWORD

nonn,easy

AUTHOR

Clark Kimberling, Oct 19 2016

STATUS

approved