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A255731 Rhonda numbers in sexagesimal number system.

%I A255731 #10 Feb 16 2025 08:33:25
%S A255731 3348,3510,6750,17430,18750,18876,18944,19475,20564,21312,26550,28280,
%T A255731 37230,38396,43940,48042,77770,88270,91224,97470,108882,111403,120046,
%U A255731 123630,181996,182646,235467,253460,260429,264735,278675,289161,295960,296055,306642
%N A255731 Rhonda numbers in sexagesimal number system.
%C A255731 See A099542 for definition of Rhonda numbers and for more links.
%H A255731 Reinhard Zumkeller, <a href="/A255731/b255731.txt">Table of n, a(n) for n = 1..1000</a>
%H A255731 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/RhondaNumber.html">Rhonda Number</a>
%H A255731 Wikipedia, <a href="http://www.wikipedia.org/wiki/Sexagesimal">Sexagesimal</a>
%e A255731 a(1) = 3348 = 55 * 60^1 + 48 * 60^0 = 2*2*3*3*3*31,
%e A255731 with 55 * 48 = 60 * (2+2+3+3+3+31) = 2640;
%e A255731 a(10) = 21312 = 5*60^2 + 55*60^1 + 12*60^0 = 2*2*2*2*2*2*3*3*37,
%e A255731 with 5 * 55 * 12 = 60 * (2+2+2+2+2+2+3+3+37) = 3300.
%o A255731 (Haskell)
%o A255731 a255731 n = a255731_list !! (n-1)
%o A255731 a255731_list = filter (rhonda 60) $ iterate z 1 where
%o A255731    z x = 1 + if r < 59 then x else 60 * z x' where (x', r) = divMod x 60
%o A255731 -- Function rhonda as in A099542.
%Y A255731 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), A255735 (base 18), A255732 (base 20), A255736 (base 30).
%Y A255731 Cf. A001414, A027746.
%Y A255731 Column k=42 of A291925.
%K A255731 nonn,base
%O A255731 1,1
%A A255731 _Reinhard Zumkeller_, Mar 05 2015