login
The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A277588 Numbers k such that k/10^m == 1 mod 10, where 10^m is the greatest power of 10 that divides n. 9
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 (list; graph; refs; listen; history; text; internal format)
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 * A022100 A041475 A041204

Adjacent sequences:  A277585 A277586 A277587 * A277589 A277590 A277591

KEYWORD

nonn,easy,base

AUTHOR

Clark Kimberling, Nov 05 2016

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified August 8 19:29 EDT 2020. Contains 336298 sequences. (Running on oeis4.)