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A062537 Nodes in riff (rooted index-functional forest) for n. 32

%I

%S 0,1,2,2,3,3,3,3,3,4,4,4,4,4,5,3,4,4,4,5,5,5,4,5,4,5,4,5,5,6,5,4,6,5,

%T 6,5,5,5,6,6,5,6,5,6,6,5,6,5,4,5,6,6,4,5,7,6,6,6,5,7,5,6,6,4,7,7,5,6,

%U 6,7,6,6,6,6,6,6,7,7,6,6,4,6,5,7,7,6,7,7,6,7,7,6,7,7,7,6,5,5,7,6,6,7,5,7,8

%N Nodes in riff (rooted index-functional forest) for n.

%C A061396(n) gives number of times n appears in this sequence.

%H Reinhard Zumkeller, <a href="/A062537/b062537.txt">Table of n, a(n) for n = 1..10000</a>

%H J. Awbrey, <a href="/A061396/a061396a.txt">Illustrations of riffs for small integers</a>

%H J. Awbrey, <a href="https://oeis.org/wiki/Riffs_and_Rotes">Riffs and Rotes</a>

%F a(Prod(p_i^e_i)) = Sum(a(i)+a(e_i)+1), product over nonzero e_i in prime factorization.

%F a(n) = sum(a(A049084(A027748(n,k)))+a(A124010(n,k))+1: k=1..A001221(n)). - _Reinhard Zumkeller_, Feb 26 2013

%t a[1] = 0; a[n_] := a[n] = Sum[{p, e} = pe; a[PrimePi[p]] + a[e] + 1, {pe, FactorInteger[n]}]; Array[a, 105] (* _Jean-Fran├žois Alcover_, Jul 26 2019 *)

%o (Haskell)

%o import Data.Function (on)

%o a062537 1 = 0

%o a062537 n = sum $ map (+ 1) $

%o zipWith ((+) `on` a062537) (map a049084 $ a027748_row n) (a124010_row n)

%o -- _Reinhard Zumkeller_, Feb 26 2013

%K nonn,easy,nice

%O 1,3

%A _David W. Wilson_, Jun 25 2001

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Last modified July 8 00:40 EDT 2020. Contains 335502 sequences. (Running on oeis4.)