# Greetings from The On-Line Encyclopedia of Integer Sequences! http://oeis.org/ Search: id:a062537 Showing 1-1 of 1 %I A062537 #29 Jul 11 2023 19:32:58 %S A062537 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 A062537 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 A062537 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 A062537 Nodes in riff (rooted index-functional forest) for n. %C A062537 A061396(n) is the number of times n appears in this sequence. %H A062537 Reinhard Zumkeller, Table of n, a(n) for n = 1..10000 %H A062537 Jon Awbrey, Illustrations of riffs for small integers. %H A062537 Jon Awbrey, Riffs and Rotes. %F A062537 a(Product(p_i^e_i)) = Sum(a(i)+a(e_i)+1), product over nonzero e_i in prime factorization. %F A062537 a(n) = Sum_{k=1..A001221(n)} (a(A049084(A027748(n,k))) + a(A124010(n,k)) + 1). - _Reinhard Zumkeller_, Feb 26 2013 %t A062537 a[1] = 0; a[n_] := a[n] = Sum[{p, e} = pe; a[PrimePi[p]] + a[e] + 1, {pe, FactorInteger[n]}]; Array[a, 105] (* _Jean-François Alcover_, Jul 26 2019 *) %o A062537 (Haskell) %o A062537 import Data.Function (on) %o A062537 a062537 1 = 0 %o A062537 a062537 n = sum $ map (+ 1) $ %o A062537 zipWith ((+) `on` a062537) (map a049084 $ a027748_row n) (a124010_row n) %o A062537 -- _Reinhard Zumkeller_, Feb 26 2013 %Y A062537 Cf. A061396. %Y A062537 Cf. A001221, A027748, A049084, A124010. %K A062537 nonn,easy,nice %O A062537 1,3 %A A062537 _David W. Wilson_, Jun 25 2001 # Content is available under The OEIS End-User License Agreement: http://oeis.org/LICENSE