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A068719 Arithmetic derivative of even numbers: a(n) = n+2*A003415(n). 7
1, 4, 5, 12, 7, 16, 9, 32, 21, 24, 13, 44, 15, 32, 31, 80, 19, 60, 21, 68, 41, 48, 25, 112, 45, 56, 81, 92, 31, 92, 33, 192, 61, 72, 59, 156, 39, 80, 71, 176, 43, 124, 45, 140, 123, 96, 49, 272, 77, 140, 91, 164, 55, 216, 87, 240, 101, 120 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Bruno Berselli, Table of n, a(n) for n = 1..1000

FORMULA

a(n) = A003415(A005843(n)).

PROG

(MAGMA) Ad:=func<h | h*(&+[Factorisation(h)[i][2]/Factorisation(h)[i][1]: i in [1..#Factorisation(h)]])>; [Ad(2*n): n in [1..60]]; // Bruno Berselli, Oct 22 2013

CROSSREFS

Cf. A003415, A005843, A068719 - A068721.

Sequence in context: A253086 A260624 A067371 * A191161 A246316 A034773

Adjacent sequences:  A068716 A068717 A068718 * A068720 A068721 A068722

KEYWORD

nonn

AUTHOR

Reinhard Zumkeller, Feb 26 2002

STATUS

approved

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Last modified April 7 09:13 EDT 2020. Contains 333300 sequences. (Running on oeis4.)