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A255735 Integers that are Rhonda numbers to base 18.

%I A255735 #13 Feb 16 2025 08:33:25
%S A255735 1470,3000,8918,17025,19402,20650,21120,22156,26522,36549,38354,43281,
%T A255735 46035,48768,54229,54528,56584,58216,58224,62238,68096,68150,73161,
%U A255735 74024,74636,87978,94041,114000,124656,132240,133926,135876,153105,153870,156621,159819
%N A255735 Integers that are Rhonda numbers to base 18.
%C A255735 See A099542 for definition of Rhonda numbers and for more links.
%H A255735 Reinhard Zumkeller, <a href="/A255735/b255735.txt">Table of n, a(n) for n = 1..1000</a>
%H A255735 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/RhondaNumber.html">Rhonda Number</a>
%e A255735 a(1) = 1470 = 4*18^2 + 9*18^1 + 12*18^0 = 2*3*5*7*7,
%e A255735 with 4 * 9 * 12 = 18 * (2+3+5+7+7) = 432;
%e A255735 a(10) = 36549 = 6*18^3 + 4*18^2 + 14*18^1 + 9*18^0 = 3*3*31*131,
%e A255735 with 6 * 4 * 14 * 9 = 18 * (3+3+31+131) = 3024.
%o A255735 (Haskell)
%o A255735 a255735 n = a255735_list !! (n-1)
%o A255735 a255735_list = filter (rhonda 18) $ iterate z 1 where
%o A255735    z x = 1 + if r < 17 then x else 18 * z x' where (x', r) = divMod x 18
%o A255735 -- Function rhonda as in A099542.
%Y A255735 Cf. Rhonda numbers to other bases: A100968 (base 4), A100969 (base 6), A100970 (base 8), A100973 (base 9), A099542 (base 10), A100971 (base 12), A100972 (base 14), A100974 (base 15), A100975 (base 16), A255732 (base 20), A255736 (base 30), A255731 (base 60), A255872.
%Y A255735 Cf. A001414, A027746.
%Y A255735 Column k=10 of A291925.
%K A255735 nonn,base
%O A255735 1,1
%A A255735 _Reinhard Zumkeller_, Mar 05 2015