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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 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Reinhard Zumkeller, Table of n, a(n) for n = 1..10000

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

Adjacent sequences:  A061423 A061424 A061425 * A061427 A061428 A061429

KEYWORD

nonn,base,easy

AUTHOR

Amarnath Murthy, May 03 2001

EXTENSIONS

More terms from Erich Friedman, May 08 2001

STATUS

approved

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Last modified January 23 22:16 EST 2020. Contains 331177 sequences. (Running on oeis4.)