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A103261 Number of partitions of 2n into parts with 10 types c^1 c^2...C^10 of each part. The even parts appear with multiplicity 1 for each type . The odd parts occur with multiplicity 2 for each part. 0
1, 20, 200, 1360, 7200, 32024, 125280, 443680, 1450240, 4435940, 12827888, 35346800, 93377920, 237675640, 585229760, 1398704736, 3253934080, 7386124520, 16392493800, 35634450320, 75992326592, 159199081600, 328027789600 (list; graph; refs; listen; history; internal format)
OFFSET

0,2

COMMENTS

This is also Sequence(A080054)^(10) or sequence(A007096)^(5)

FORMULA

G.f.:(theta_4(0, x^2)/theta_4(0, x))^10= (theta_3(0, x)/theta_4(0, x))^5.

EXAMPLE

a(4)=200 because we have 10 types of 4, 45 ways of writing 4 in terms of ten of 2's only or ten of 11's only and 100 ways of writing 2's combined with 11's so the total number of ways of writng 4 is 200.

MAPLE

series(product(((1+x^k)*(1-x^(2*k)))^(10)/((1-x^k)*(1+x^(2*k)))^(10), k=1..100), x=0, 100);

CROSSREFS

Cf. A080054, A007096.

Sequence in context: A008420 A045758 A035474 * A120796 A120787 A099197

Adjacent sequences:  A103258 A103259 A103260 * A103262 A103263 A103264

KEYWORD

nonn

AUTHOR

Noureddine Chair (n.chair(AT)rocketmail.com), Feb 16 2005

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Last modified February 17 21:13 EST 2012. Contains 206085 sequences.