VOOZH about

URL: https://oeis.org/A255731

⇱ A255731 - OEIS

login
A255731
Rhonda numbers in sexagesimal number system.
14
3348, 3510, 6750, 17430, 18750, 18876, 18944, 19475, 20564, 21312, 26550, 28280, 37230, 38396, 43940, 48042, 77770, 88270, 91224, 97470, 108882, 111403, 120046, 123630, 181996, 182646, 235467, 253460, 260429, 264735, 278675, 289161, 295960, 296055, 306642
OFFSET
1,1
COMMENTS
See A099542 for definition of Rhonda numbers and for more links.
LINKS
Eric Weisstein's World of Mathematics, Rhonda Number
Wikipedia, Sexagesimal
EXAMPLE
a(1) = 3348 = 55 * 60^1 + 48 * 60^0 = 2*2*3*3*3*31,
with 55 * 48 = 60 * (2+2+3+3+3+31) = 2640;
a(10) = 21312 = 5*60^2 + 55*60^1 + 12*60^0 = 2*2*2*2*2*2*3*3*37,
with 5 * 55 * 12 = 60 * (2+2+2+2+2+2+3+3+37) = 3300.
PROG
(Haskell)
a255731 n = a255731_list !! (n-1)
a255731_list = filter (rhonda 60) $ iterate z 1 where
z x = 1 + if r < 59 then x else 60 * z x' where (x', r) = divMod x 60
-- 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), A255732 (base 20), A255736 (base 30).
Column k=42 of A291925.
Sequence in context: A054356 A358312 A348525 * A204884 A204880 A151601
KEYWORD
nonn,base
AUTHOR
Reinhard Zumkeller, Mar 05 2015
STATUS
approved