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A277589
Numbers k such that k/10^m == 2 mod 10, where 10^m is the greatest power of 10 that divides n.
10
2, 12, 20, 22, 32, 42, 52, 62, 72, 82, 92, 102, 112, 120, 122, 132, 142, 152, 162, 172, 182, 192, 200, 202, 212, 220, 222, 232, 242, 252, 262, 272, 282, 292, 302, 312, 320, 322, 332, 342, 352, 362, 372, 382, 392, 402, 412, 420, 422, 432, 442, 452, 462, 472
OFFSET
1,1
COMMENTS
Positions of 2 in A065881.
Numbers having 2 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
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 *)
PROG
(PARI) is(n)=n && n/10^valuation(n, 10)%10==2 \\ Charles R Greathouse IV, Jan 31 2017
CROSSREFS
KEYWORD
nonn,easy,base
AUTHOR
Clark Kimberling, Nov 05 2016
STATUS
approved