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A247045 Triangle read by rows: T(n,k) = least number m > 0 such that m^k in base n contains exactly k distinct digits, 1 <= k <= n.

%I A247045 #16 Feb 14 2017 11:09:07
%S A247045 1,1,2,1,3,4,1,2,3,5,1,3,3,6,12,1,3,5,7,7,15,1,3,5,9,5,17,15,1,4,5,10,
%T A247045 9,7,11,33,1,3,5,7,11,19,14,16,53,1,4,5,6,7,13,13,14,21,36,1,4,5,7,10,
%U A247045 8,12,12,16,42,41,1,4,6,16,11,8,19,19,16,28,35,55,1,4,6,9,9,14,10,18,14
%N A247045 Triangle read by rows: T(n,k) = least number m > 0 such that m^k in base n contains exactly k distinct digits, 1 <= k <= n.
%H A247045 Indranil Ghosh, <a href="/A247045/b247045.txt">Rows 1..36 of triangle, flattened</a>
%e A247045 T(n,k) is given by (row n corresponds to base n):
%e A247045 1;
%e A247045 1, 2;
%e A247045 1, 3, 4;
%e A247045 1, 2, 3,  5;
%e A247045 1, 3, 3,  6, 12;
%e A247045 1, 3, 5,  7,  7, 15;
%e A247045 1, 3, 5,  9,  5, 17, 15;
%e A247045 1, 4, 5, 10,  9,  7, 11, 33;
%e A247045 1, 3, 5,  7, 11, 19, 14, 16, 53;
%e A247045 1, 4, 5,  6,  7, 13, 13, 14, 21, 36; (base 10)
%e A247045 1, 4, 5,  7, 10,  8, 12, 12, 16, 42, 41;
%e A247045 Example: T(7,3) = 5 means that 5 is the smallest number such that 5^3 in base 7 (which is 125 in base 7 = 236) has 3 distinct digits (2, 3, and 6).
%o A247045 (PARI)
%o A247045 print1(1,", ");n=2;while(n<20,m=1;for(k=1,n,while(m,d=digits(m^k,n);if(#vecsort(d,,8)!=k,m++);if(#vecsort(d,,8)==k,print1(m,", ");m=1;break)));n++)
%Y A247045 Cf. A016069, A155146, A155150.
%K A247045 nonn,base,tabl
%O A247045 1,3
%A A247045 _Derek Orr_, Sep 10 2014