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A100975 Integers that are Rhonda numbers to base 16.

%I A100975 #12 Feb 16 2025 08:32:55
%S A100975 1000,1134,6776,15912,19624,20043,20355,23946,26296,29070,31906,32292,
%T A100975 34236,34521,36465,39066,50055,50986,52341,54340,58088,59541,75867,
%U A100975 85870,87150,88182,93058,95944,99674,101460,109650,109810,119480,124500
%N A100975 Integers that are Rhonda numbers to base 16.
%C A100975 See A099542 for definition of Rhonda numbers and for some links.
%H A100975 Reinhard Zumkeller, <a href="/A100975/b100975.txt">Table of n, a(n) for n = 1..1000</a>
%H A100975 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/RhondaNumber.html">Rhonda Number</a>
%H A100975 Wikipedia, <a href="http://www.wikipedia.org/wiki/Hexadecimal">Hexadecimal</a>
%e A100975 The product of the base 16 digits of 1000 is 3*14*8=336. The sum of the prime factors of 1000 is 3*2+3*5=21. 336=16*21 and so 1000 is a Rhonda number to base 16.
%o A100975 (Haskell)
%o A100975 a100975 n = a100975_list !! (n-1)
%o A100975 a100975_list = filter (rhonda 16) $ iterate z 1 where
%o A100975    z x = 1 + if r < 15 then x else 16 * z x' where (x', r) = divMod x 16
%o A100975 -- Function rhonda as in A099542.
%o A100975 -- _Reinhard Zumkeller_, Mar 07 2015
%Y A100975 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), A255735 (base 18), A255732 (base 20), A255736 (base 30), A255731 (base 60).
%Y A100975 Cf. A001414, A027746, A255872.
%Y A100975 Column k=9 of A291925.
%K A100975 easy,nonn,base
%O A100975 1,1
%A A100975 Mark Hudson (mrmarkhudson(AT)hotmail.com), Nov 25 2004
%E A100975 Offset fixed by _Reinhard Zumkeller_, Mar 05 2015