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A037032 Total number of prime parts in all partitions of n. 7
0, 1, 2, 4, 7, 13, 20, 32, 48, 73, 105, 153, 214, 302, 415, 569, 767, 1034, 1371, 1817, 2380, 3110, 4025, 5199, 6659, 8512, 10806, 13684, 17229, 21645, 27049, 33728, 41872, 51863, 63988, 78779, 96645, 118322, 144406, 175884, 213617, 258957 (list; graph; refs; listen; history; internal format)
OFFSET

1,3

FORMULA

a(n) = Sum_{k=1..n} A001221(k)*A000041(n-k). - Vladeta Jovovic (vladeta(AT)eunet.rs), Aug 22 2002

EXAMPLE

Contribution from Omar E. Pol, Nov 20 2011 (Start):

For n = 6 we have:

--------------------------------------

.                        Number of

Partitions              prime parts

--------------------------------------

6 .......................... 0

3 + 3 ...................... 2

4 + 2 ...................... 1

2 + 2 + 2 .................. 3

5 + 1 ...................... 1

3 + 2 + 1 .................. 2

4 + 1 + 1 .................. 0

2 + 2 + 1 + 1 .............. 2

3 + 1 + 1 + 1 .............. 1

2 + 1 + 1 + 1 + 1 .......... 1

1 + 1 + 1 + 1 + 1 + 1 ...... 0

------------------------------------

Total ..................... 13

So a(6) = 13. (End)

MAPLE

with(combinat): a:=proc(n) local P, c, j, i: P:=partition(n): c:=0: for j from 1 to numbpart(n) do for i from 1 to nops(P[j]) do if isprime(P[j][i])=true then c:=c+1 else c:=c fi: od: od: c: end: seq(a(n), n=1..42); - Emeric Deutsch (deutsch(AT)duke.poly.edu), Mar 30 2006

CROSSREFS

Cf. A000041.

Sequence in context: A164901 A109853 A112997 * A165753 A205183 A090752

Adjacent sequences:  A037029 A037030 A037031 * A037033 A037034 A037035

KEYWORD

nonn

AUTHOR

G. L. Honaker, Jr. (honak3r(AT)gmail.com)

EXTENSIONS

More terms from Naohiro Nomoto (n_nomoto(AT)yabumi.com), Apr 19 2002

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Last modified February 17 09:41 EST 2012. Contains 206009 sequences.