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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
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
Sequence in context: A064039 A255536 A298849 * A339138 A022100 A041475
KEYWORD
nonn,easy,base
AUTHOR
Clark Kimberling, Nov 05 2016
STATUS
approved

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Last modified May 29 11:04 EDT 2024. Contains 372938 sequences. (Running on oeis4.)