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A068981
Arithmetic derivative of n*prime(n).
0
1, 5, 8, 32, 16, 71, 24, 236, 147, 213, 42, 604, 54, 401, 391, 1712, 76, 1299, 86, 1724, 751, 1049, 106, 3940, 995, 1541, 2808, 3452, 138, 3533, 158, 10512, 1951, 2675, 1823, 9096, 194, 3461, 2711, 11804, 220, 7463, 234
OFFSET
1,2
COMMENTS
a(n) = A003415(A033286(n))= A003415(n*A000040(n)).
FORMULA
a(n) = n + A000040(n)*A003415(n).
EXAMPLE
a(10) = A003415(A033286(10)) = A003415(A000040(10)*10) = A003415(29*10) = A003415(29)*10 + 29*A003415(10) = 1*10 + 29*(2*1 + 1*5) = 10 + 29*7 = 213.
CROSSREFS
Sequence in context: A049373 A304647 A002536 * A099631 A199396 A275003
KEYWORD
nonn
AUTHOR
Reinhard Zumkeller, Apr 01 2002
STATUS
approved