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A061426
Geometric mean of the digits = 2. In other words, the product of the digits is = 2^k where k is the number of digits.
8
2, 14, 22, 41, 118, 124, 142, 181, 214, 222, 241, 412, 421, 811, 1128, 1144, 1182, 1218, 1224, 1242, 1281, 1414, 1422, 1441, 1812, 1821, 2118, 2124, 2142, 2181, 2214, 2222, 2241, 2412, 2421, 2811, 4114, 4122, 4141, 4212, 4221, 4411, 8112, 8121, 8211
OFFSET
1,1
LINKS
EXAMPLE
124 is a term as the geometric mean of digits is (1*2*4) = 8 = 2^3.
PROG
(Haskell)
a061426 n = a061426_list !! (n-1)
a061426_list = g [1] where
g ds = if product ds == 2 ^ length ds
then foldr (\d v -> 10 * v + d) 0 ds : g (s ds) else g (s ds)
s [] = [1]; s (8:ds) = 1 : s ds; s (d:ds) = 2*d : ds
-- Reinhard Zumkeller, Jan 13 2014
CROSSREFS
Cf. A061427-A061430. A069512 gives another version.
Cf. A028846.
Sequence in context: A073143 A066613 A074312 * A190045 A247035 A069512
KEYWORD
nonn,base,easy
AUTHOR
Amarnath Murthy, May 03 2001
EXTENSIONS
More terms from Erich Friedman, May 08 2001
STATUS
approved