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A100030 Bisection of A008472. 0
2, 2, 5, 2, 7, 5, 9, 2, 5, 7, 13, 5, 15, 9, 10, 2, 19, 5, 21, 7, 12, 13, 25, 5, 7, 15, 5, 9, 31, 10, 33, 2, 16, 19, 14, 5, 39, 21, 18, 7, 43, 12, 45, 13, 10, 25, 49, 5, 9, 7, 22, 15, 55, 5, 18, 9, 24, 31, 61, 10, 63, 33, 12, 2, 20, 16, 69, 19, 28, 14, 73, 5, 75, 39, 10, 21, 20, 18, 81, 7, 5 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

The sum of the distinct primes dividing 2n. - Emeric Deutsch, Mar 11 2005

LINKS

Table of n, a(n) for n=1..81.

EXAMPLE

a(6)=5 because 12 = 2^2*3 and 2+3 = 5.

MAPLE

with(numtheory): a:=proc(n) local b: b:=convert(factorset(2*n), list): add(b[j], j=1..nops(b)) end: seq(a(n), n=1..90); # Emeric Deutsch, Mar 11 2005

CROSSREFS

Sequence in context: A029648 A126103 A316895 * A029603 A204202 A025124

Adjacent sequences:  A100027 A100028 A100029 * A100031 A100032 A100033

KEYWORD

nonn,easy

AUTHOR

N. J. A. Sloane, Nov 20 2004

EXTENSIONS

More terms from Emeric Deutsch, Mar 11 2005

STATUS

approved

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Last modified October 19 04:40 EDT 2019. Contains 328211 sequences. (Running on oeis4.)