A215884 Written in base 5, n ends in a(n) consecutive nonzero digits.

0, 1, 1, 1, 1, 0, 2, 2, 2, 2, 0, 2, 2, 2, 2, 0, 2, 2, 2, 2, 0, 2, 2, 2, 2, 0, 1, 1, 1, 1, 0, 3, 3, 3, 3, 0, 3, 3, 3, 3, 0, 3, 3, 3, 3, 0, 3, 3, 3, 3, 0, 1, 1, 1, 1, 0, 3, 3, 3, 3, 0, 3, 3, 3, 3, 0, 3, 3, 3, 3, 0, 3, 3, 3, 3, 0, 1, 1, 1, 1, 0, 3, 3, 3, 3, 0, 3, 3, 3, 3, 0, 3, 3, 3, 3, 0, 3, 3, 3, 3, 0, 1, 1, 1, 1, 0, 3

Offset: 0

Author

M. F. Hasler, Aug 25 2012

Keywords

• nonn
• base

Comments

Sequences A215879, A215883 and A215887 are the base 3, 4 and 10 analogs, while the base 2 analog of this sequence coincides (up to a shift in the index) with the 2-adic valuation A007814, cf. comments there.

Examples

			The numbers 24,...,31 are written in base 5 as 44,100,101,102,103,104,110,111 and thus end in a string of a(24..31)=2,0,1,1,1,1,0,3 nonzero digits.
		

Links

• Harvey P. Dale, Table of n, a(n) for n = 0..1000

Programs

Mathematica

cnzd[n_]:=Module[{c=Split[If[#>0,1,0]&/@IntegerDigits[n,5]]},If[FreeQ[ c[[-1]],0],Total[c[[-1]]],0]]; Array[cnzd,120,0] (* Harvey P. Dale, Jan 03 2023 *)

PARI

a(n,b=5)=n=divrem(n,b); for(c=0,9e9,n[2]||return(c); n=divrem(n[1],b))

PARI

a(n)=my(k);while(n%5,n\=5;k++);k \\ Charles R Greathouse IV, Sep 26 2013