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A100975
Integers that are Rhonda numbers to base 16.
17
1000, 1134, 6776, 15912, 19624, 20043, 20355, 23946, 26296, 29070, 31906, 32292, 34236, 34521, 36465, 39066, 50055, 50986, 52341, 54340, 58088, 59541, 75867, 85870, 87150, 88182, 93058, 95944, 99674, 101460, 109650, 109810, 119480, 124500
OFFSET
1,1
COMMENTS
See A099542 for definition of Rhonda numbers and for some links.
LINKS
Eric Weisstein's World of Mathematics, Rhonda Number
Wikipedia, Hexadecimal
EXAMPLE
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.
PROG
(Haskell)
a100975 n = a100975_list !! (n-1)
a100975_list = filter (rhonda 16) $ iterate z 1 where
z x = 1 + if r < 15 then x else 16 * z x' where (x', r) = divMod x 16
-- Function rhonda as in A099542.
-- Reinhard Zumkeller, Mar 07 2015
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), A255735 (base 18), A255732 (base 20), A255736 (base 30), A255731 (base 60).
Column k=9 of A291925.
Sequence in context: A291346 A191753 A033830 * A105276 A145517 A342975
KEYWORD
easy,nonn,base
AUTHOR
Mark Hudson (mrmarkhudson(AT)hotmail.com), Nov 25 2004
EXTENSIONS
Offset fixed by Reinhard Zumkeller, Mar 05 2015
STATUS
approved