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%I #9 Jan 31 2017 00:58:51
%S 7,17,27,37,47,57,67,70,77,87,97,107,117,127,137,147,157,167,170,177,
%T 187,197,207,217,227,237,247,257,267,270,277,287,297,307,317,327,337,
%U 347,357,367,370,377,387,397,407,417,427,437,447,457,467,470,477,487
%N Numbers k such that k/10^m == 7 mod 10, where 10^m is the greatest power of 10 that divides n.
%C Positions of 7 in A065881.
%C Numbers having 7 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 Clark Kimberling, <a href="/A277594/b277594.txt">Table of n, a(n) for n = 1..10000</a>
%t z = 460; a[b_] := Table[Mod[n/b^IntegerExponent[n, b], b], {n, 1, z}]
%t p[b_, d_] := Flatten[Position[a[b], d]]
%t p[10, 1] (* A277588 *)
%t p[10, 2] (* A277589 *)
%t p[10, 3] (* A277590 *)
%t p[10, 4] (* A277591 *)
%t p[10, 5] (* A277592 *)
%t p[10, 6] (* A277593 *)
%t p[10, 7] (* A277594 *)
%t p[10, 8] (* A277595 *)
%t p[10, 9] (* A277596 *)
%o (PARI) is(n)=n && n/10^valuation(n,10)%10==7 \\ _Charles R Greathouse IV_, Jan 31 2017
%Y Cf. A277588-A277593, A277595-A277596.
%K nonn,easy,base
%O 1,1
%A _Clark Kimberling_, Nov 07 2016
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