A072085 - OEIS

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A072085

a(n) = A072084(A072084(n)).

1, 1, 1, 1, 1, 1, 2, 1, 1, 1, 2, 1, 2, 2, 1, 1, 1, 1, 2, 1, 2, 2, 1, 1, 1, 2, 1, 2, 1, 1, 2, 1, 2, 1, 2, 1, 2, 2, 2, 1, 2, 2, 1, 2, 1, 1, 2, 1, 4, 1, 1, 2, 1, 1, 2, 2, 2, 1, 2, 1, 2, 2, 2, 1, 2, 2, 2, 1, 1, 2, 1, 1, 2, 2, 1, 2, 4, 2, 2, 1, 1, 2, 1, 2, 1, 1, 1, 2, 1, 1, 4, 1, 2, 2, 2, 1

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

OFFSET

1,7

LINKS

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

MATHEMATICA

b[n_] := Times @@ Power @@@ (FactorInteger[n] /. {p_Integer, e_} :> {DigitCount[p, 2, 1], e}); a[n_] := b[b[n]]; Array[a, 100] (* Jean-François Alcover, Feb 09 2018 *)

PROG

(Haskell)

a072085 = a072084 . a072084 -- Reinhard Zumkeller, Feb 10 2013

CROSSREFS

Cf. A072086.

Sequence in context: A369917 A319608 A230850 * A054868 A352517 A347981

Adjacent sequences: A072082 A072083 A072084 * A072086 A072087 A072088

KEYWORD

nonn,mult

AUTHOR

Reinhard Zumkeller, Jun 14 2002

STATUS

approved