A277588 Numbers k such that k/10^m == 1 mod 10, where 10^m is the greatest power of 10 that divides n.

1, 10, 11, 21, 31, 41, 51, 61, 71, 81, 91, 100, 101, 110, 111, 121, 131, 141, 151, 161, 171, 181, 191, 201, 210, 211, 221, 231, 241, 251, 261, 271, 281, 291, 301, 310, 311, 321, 331, 341, 351, 361, 371, 381, 391, 401, 410, 411, 421, 431, 441, 451, 461, 471

Offset

1,2

Comments

Positions of 1 in A065881.

Numbers having 1 as rightmost nonzero digit in base 10. This is one sequence in a 10-way splitting of the positive integers; the other nine are indicated in the Mathematica program.

Links

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

Maple

M:= 4: # to get all terms with <= M digits
A:= sort([seq(seq(10^d*(10*x+1), x=0..10^(M-1-d)-1), d=0..M-2)]); # Robert Israel, Nov 07 2016

Mathematica

z = 460; a[b_] := Table[Mod[n/b^IntegerExponent[n, b], b], {n, 1, z}]
p[b_, d_] := Flatten[Position[a[b], d]]
p[10, 1] (* A277588 *)
p[10, 2] (* A277589 *)
p[10, 3] (* A277590 *)
p[10, 4] (* A277591 *)
p[10, 5] (* A277592 *)
p[10, 6] (* A277593 *)
p[10, 7] (* A277594 *)
p[10, 8] (* A277595 *)
p[10, 9] (* A277596 *)
f[n_] := Block[{m = n}, While[ Mod[m, 10] == 0, m /= 10]; Mod[m, 10]]; Flatten@ Position[ Array[f, 500], 1] (* Robert G. Wilson v, Nov 06 2016 *)

Prog

(PARI) is(n)=n && n/10^valuation(n, 10)%10==1 \\ Charles R Greathouse IV, Jan 31 2017

Crossrefs

Cf. A277589-A277596.

Sequence in context: A064039 A255536 A298849 * A339138 A022100 A041475

Adjacent sequences: A277585 A277586 A277587 * A277589 A277590 A277591

Keyword

nonn,easy,base

Author

Clark Kimberling, Nov 05 2016

Status

approved