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A181674 Number of partitions of n into a primorial and a semiprime. 0
0, 0, 0, 0, 1, 1, 1, 1, 0, 2, 2, 2, 0, 0, 2, 3, 1, 0, 0, 1, 1, 1, 2, 1, 0, 1, 3, 2, 0, 0, 1, 1, 0, 2, 2, 3, 1, 0, 3, 4, 2, 0, 0, 2, 2, 0, 1, 1, 0, 1, 2, 3, 1, 0, 2, 2, 2, 1, 2, 1, 1, 0, 3, 3, 1, 1, 1, 2, 1, 1, 2, 0, 0, 0, 2, 2, 0, 1, 2, 1, 1, 0, 2, 1, 1, 1, 3, 4, 1, 0, 1, 3, 2, 1, 3, 2, 2, 0, 2, 1, 1, 0, 0, 1, 0 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,10

COMMENTS

Number of ways of writing n=k+m where k primorial and m semiprime. The number of decompositions of n into an unordered sum of primorial number and semiprime number.

Conjecture: Average order is Theta(log log n). -Charles R Greathouse IV, May 25, 2011

LINKS

Table of n, a(n) for n=1..105.

EXAMPLE

a(10)=2 because 10(natural)=6(primorial)+4(semiprime)=1(primorial)+9(semiprime).

CROSSREFS

Cf. A001358, A002110, A100949, A175933.

Sequence in context: A178045 A037864 A285635 * A181676 A262048 A034852

Adjacent sequences:  A181671 A181672 A181673 * A181675 A181676 A181677

KEYWORD

nonn

AUTHOR

Juri-Stepan Gerasimov, Nov 04 2010

STATUS

approved

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Last modified October 19 17:55 EDT 2018. Contains 316376 sequences. (Running on oeis4.)