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A145574 Array a(n,m) for number of partitions of n>=2 with m parts having no part 1. Hence m=1..floor(n/2). +0
2
1, 1, 1, 1, 1, 1, 1, 2, 1, 1, 2, 1, 1, 3, 2, 1, 1, 3, 3, 1, 1, 4, 4, 2, 1, 1, 4, 5, 3, 1, 1, 5, 7, 5, 2, 1, 1, 5, 8, 6, 3, 1, 1, 6, 10, 9, 5, 2, 1, 1, 6, 12, 11, 7, 3, 1, 1, 7, 14, 15, 10, 5, 2, 1, 1, 7, 16, 18, 13, 7, 3, 1, 1, 8, 19, 23, 18, 11, 5, 2, 1, 1, 8, 21, 27, 23, 14, 7, 3, 1, 1, 9, 24, 34, 30 (list; graph; listen)
OFFSET

2,8

COMMENT

The row lengths sequence is floor(n/2) = [1,1,2,2,3,3,4,4,...], see A008619(n-1), n>=2.

Obtained from the characteristic partition array A145573 by summing in row n>=2 over entries belonging to like parts number m.

The column sequences give A000012, A004526, A001399, A001400, A001401, A001402, A026813 for m=1..7.

LINKS

W. Lang, M. Sjodahl First 20 rows of the array and row sums.

FORMULA

a(n,m)=sum over entries of A145573(n,k) array which belong to partitions with part number m, for m=1..floor(n/2)). Note that partitions with parts number m>floor(n/2) have always at least one part 1.

EXAMPLE

[1];[1];[1,1];[1,1];[1,2,1];[1,2,1];[1,3,2,1];[1,3,3,1];[1,4,4,2,1],...

CROSSREFS

Cf. A145573, A002865 (row sums).

Sequence in context: A078770 A072038 A108316 this_sequence A056138 A067594 A089533

Adjacent sequences: A145571 A145572 A145573 this_sequence A145575 A145576 A145577

KEYWORD

nonn,easy,tabf

AUTHOR

Wolfdieter Lang (wolfdieter.lang(AT)physik.uni-karlsruhe.de) and Malin Sjodahl (malin.sjodahl(AT)physik.uni-karlsruhe.de) Mar 06 2009

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Last modified December 19 12:50 EST 2009. Contains 171053 sequences.


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