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A068720
Arithmetic derivative of squares: a(n) = 2*n*A003415(n).
9
0, 4, 6, 32, 10, 60, 14, 192, 108, 140, 22, 384, 26, 252, 240, 1024, 34, 756, 38, 960, 420, 572, 46, 2112, 500, 780, 1458, 1792, 58, 1860, 62, 5120, 924, 1292, 840, 4320, 74, 1596, 1248, 5440, 82, 3444, 86, 4224, 3510, 2300, 94
OFFSET
1,2
COMMENTS
a(n) = A235711(2*n). - Reinhard Zumkeller, Mar 18 2014
LINKS
FORMULA
a(n) = A003415(n^2) = 2*n*A003415(n).
PROG
(Magma) Ad:=func<h | h*(&+[Factorisation(h)[i][2]/Factorisation(h)[i][1]: i in [1..#Factorisation(h)]])>; [0] cat [Ad(n^2): n in [2..50]]; // Bruno Berselli, Oct 22 2013
(Haskell)
a068720 = a003415 . a000290 -- Reinhard Zumkeller, Mar 18 2014
CROSSREFS
KEYWORD
nonn
AUTHOR
Reinhard Zumkeller, Feb 26 2002
STATUS
approved