A100970 Integers n that are Rhonda numbers to base 8.

1836, 6318, 6622, 10530, 14500, 14739, 17655, 18550, 25398, 25956, 30562, 39215, 39325, 50875, 51429, 52887, 55611, 56420, 58548, 59731, 60604, 72358, 74620, 76581, 78780, 81370, 84180, 85949, 103350, 103788, 108750, 112914, 118233

Offset

1,1

Comments

See A099542 for definition of Rhonda numbers and some links.

Links

Reinhard Zumkeller, Table of n, a(n) for n = 1..1000

Eric Weisstein's World of Mathematics, Rhonda Number

Wikipedia, Octal

Example

Product of base 8 digits of 1836 is 3*4*5*4=240 and sum of prime factors of 1826 is 2*2+3*3+17=30 and 240=8*30.

Mathematica

rhda8Q[n_]:=Times@@IntegerDigits[n, 8]==8*Total[Times@@@FactorInteger[n]]; Select[Range[120000], rhda8Q] (* Harvey P. Dale, Jul 10 2021 *)

Prog

(Haskell)
a100970 n = a100970_list !! (n-1)
a100970_list = filter (rhonda 8) a255805_list
-- Function rhonda as in A099542.
-- Reinhard Zumkeller, Mar 08 2015

Crossrefs

Cf. Rhonda numbers to other bases: A100968 (base 4), A100969 (base 6), 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), A255731 (base 60), see also A255872.

Cf. A001414, A027746, A007094, subsequence of A255805.

Column k=3 of A291925.

Sequence in context: A185484 A133539 A234492 * A159202 A238294 A274683

Adjacent sequences: A100967 A100968 A100969 * A100971 A100972 A100973

Keyword

easy,nonn,base

Author

Mark Hudson (mrmarkhudson(AT)hotmail.com), Nov 24 2004

Status

approved