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A103265 Number of partitions of n in which both even and odd square parts occur in 2 forms c, c* and with multiplicity 1. There no restriction on parts which are twice squares. 0
1, 2, 2, 2, 4, 6, 6, 6, 8, 12, 14, 14, 16, 22, 26, 26, 30, 38, 44, 46, 52, 62, 70, 74, 80, 96, 110, 116, 124, 146, 166, 174, 186, 210, 238, 254, 272, 302, 338, 362, 384, 426, 470, 502, 532, 588, 646, 686, 726, 792, 872, 926, 980, 1062 (list; graph; refs; listen; history; internal format)
OFFSET

0,2

FORMULA

G.f.: product_{k>0}((1+x^k^2)/(1-x^k^2)).

EXAMPLE

E.g. a(8)=8 because 8 can be written as 8, 44*, 422, 4*22, 4211*, 4*211*, 2222, 22211*.

MAPLE

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

CROSSREFS

Sequence in context: A152968 A086420 A170887 * A008238 A096575 A002722

Adjacent sequences:  A103262 A103263 A103264 * A103266 A103267 A103268

KEYWORD

easy,nonn

AUTHOR

Noureddine Chair (n.chair(AT)rocketmail.com.com), Feb 27 2005

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Last modified February 14 09:48 EST 2012. Contains 205614 sequences.