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%I #21 Oct 21 2017 21:43:21
%S 10206,855,11935,1836,1029,12150,15540,6318,3813,16031,1568,21054,
%T 6622,5577,45030,560,2835,25331,10530,7040,94185,11475,800,4752,44360,
%U 14500,7304,113022,2392,18655,3993,5265,44660,14739,15104,114415,1000,2472,20565,4425,5439,44733,17655,19136,191149
%N A(n,k) is the n-th Rhonda number to base A002808(k), the k-th composite number; square array A(n,k), n>=1, k>=1, read by antidiagonals.
%C Integer m is Rhonda number to base b if the product of its base-b digits divided by b is equal to the integer log of m, A001414(m). This can only happen if b is a composite number, b in {A002808}.
%H Alois P. Heinz, <a href="/A291925/b291925.txt">Antidiagonals n = 1..141, flattened</a>
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/RhondaNumber.html">Rhonda Number</a>
%e A(1,2) = 855 is the first and smallest term of column k=2. The second composite number is A002808(2) = 6. 855 = (((3*6)+5)*6+4)*6+3 = 3543_6 = 3*3*5*19. And (3*5*4*3)/6 = A001414(855) = 3+3+5+19 = 30.
%e Square array A(n,k) begins:
%e : 10206, 855, 1836, 15540, 1568, 560, 11475, ...
%e : 11935, 1029, 6318, 21054, 2835, 800, 18655, ...
%e : 12150, 3813, 6622, 25331, 4752, 3993, 20565, ...
%e : 16031, 5577, 10530, 44360, 5265, 4425, 29631, ...
%e : 45030, 7040, 14500, 44660, 5439, 4602, 31725, ...
%e : 94185, 7304, 14739, 44733, 5664, 4888, 45387, ...
%e : 113022, 15104, 17655, 47652, 5824, 7315, 58404, ...
%Y Columns k=1-11,19,42 give: A100968, A100969, A100970, A100973, A099542, A100971, A100972, A100974, A100975, A255735, A255732, A255736, A255731.
%Y Row n=1 gives A255872.
%Y Main diagonal gives A255880.
%Y Cf. A001414, A002808, A100987, A100988, A217986.
%K nonn,tabl,look
%O 1,1
%A _Alois P. Heinz_, Sep 05 2017
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