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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.

%I A277589 #9 Jan 31 2017 01:00:27
%S A277589 2,12,20,22,32,42,52,62,72,82,92,102,112,120,122,132,142,152,162,172,
%T A277589 182,192,200,202,212,220,222,232,242,252,262,272,282,292,302,312,320,
%U A277589 322,332,342,352,362,372,382,392,402,412,420,422,432,442,452,462,472
%N A277589 Numbers k such that k/10^m == 2 mod 10, where 10^m is the greatest power of 10 that divides n.
%C A277589 Positions of 2 in A065881.
%C A277589 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.
%H A277589 Clark Kimberling, <a href="/A277589/b277589.txt">Table of n, a(n) for n = 1..10000</a>
%t A277589 z = 460; a[b_] := Table[Mod[n/b^IntegerExponent[n, b], b], {n, 1, z}]
%t A277589 p[b_, d_] := Flatten[Position[a[b], d]]
%t A277589 p[10, 1] (* A277588 *)
%t A277589 p[10, 2] (* A277589 *)
%t A277589 p[10, 3] (* A277590 *)
%t A277589 p[10, 4] (* A277591 *)
%t A277589 p[10, 5] (* A277592 *)
%t A277589 p[10, 6] (* A277593 *)
%t A277589 p[10, 7] (* A277594 *)
%t A277589 p[10, 8] (* A277595 *)
%t A277589 p[10, 9] (* A277596 *)
%o A277589 (PARI) is(n)=n && n/10^valuation(n,10)%10==2 \\ _Charles R Greathouse IV_, Jan 31 2017
%Y A277589 Cf. A277588, A277590-A277596.
%K A277589 nonn,easy,base
%O A277589 1,1
%A A277589 _Clark Kimberling_, Nov 05 2016