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A100972
Integers that are Rhonda numbers to base 14.
16
11475, 18655, 20565, 29631, 31725, 45387, 58404, 58667, 59950, 63945, 67525, 68904, 91245, 99603, 125543, 135196, 141141, 148645, 149575, 168270, 175577, 204611, 207230, 237540, 240006, 240787, 275429, 287950, 321867, 338709, 358984
OFFSET
1,1
COMMENTS
See sequence A099542 for definition of Rhonda numbers and for some links.
LINKS
Eric Weisstein's World of Mathematics, Rhonda Number
EXAMPLE
The product of the base 14 digits of 11475 is 4*2*7*9=504, the sum of the prime factors of 11475 is 3*3+2*5+17=46 and 504=14*36, so 11475 is a Rhonda number to base 14.
PROG
(Haskell)
a100972 n = a100972_list !! (n-1)
a100972_list = filter (rhonda 14) $ iterate z 1 where
z x = 1 + if r < 13 then x else 14 * z x' where (x', r) = divMod x 14
-- 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), A100974 (base 15), A100975 (base 16), A255735 (base 18), A255732 (base 20), A255736 (base 30), A255731 (base 60).
Column k=7 of A291925.
Sequence in context: A204569 A023071 A349746 * A293371 A251879 A201048
KEYWORD
easy,nonn,base
AUTHOR
Mark Hudson (mrmarkhudson(AT)hotmail.com), Nov 25 2004
STATUS
approved