OFFSET
1,1
COMMENTS
See A099542 for definition of Rhonda numbers and for more links.
LINKS
Reinhard Zumkeller, Table of n, a(n) for n = 1..1000
Eric Weisstein's World of Mathematics, Rhonda Number
Wikipedia, Vigesimal
EXAMPLE
a(1) = 1815 = 4*20^2 + 10*20^1 + 15*20^0 = 3*5*11*11,
with 4 * 10 * 15 = 20 * (3+5+11+11) = 600;
a(10) = 44165 = 5*20^3 + 10*20^2 + 8*20^1 + 5*20^0 = 5*11*11*73,
with 5 * 10 * 8 * 5 = 20 * (5+11+11+73) = 2000.
PROG
(Haskell)
a255732 n = a255732_list !! (n-1)
a255732_list = filter (rhonda 20) $ iterate z 1 where
z x = 1 + if r < 29 then x else 30 * z x' where (x', r) = divMod x 30
-- Function rhonda as in A099542.
CROSSREFS
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), A255736 (base 30), A255731 (base 60), see also A255872.
Column k=11 of A291925.
KEYWORD
nonn,base
AUTHOR
Reinhard Zumkeller, Mar 05 2015
STATUS
approved