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A100926 Number of partitions of n into parts free of odd squares and the only number with multiplicity in the unrestricted partitions is the number 2. 2
1, 0, 1, 1, 2, 2, 3, 4, 5, 6, 8, 10, 12, 15, 18, 23, 27, 33, 40, 48, 57, 69, 81, 97, 113, 134, 157, 184, 214, 250, 290, 337, 389, 451, 519, 598, 688, 789, 904, 1035, 1181, 1348, 1535, 1746, 1983, 2250, 2549, 2885, 3261, 3682, 4154, 4680, 5268, 5923, 6656, 7468 (list; graph; refs; listen; history; internal format)
OFFSET

1,5

COMMENTS

This is also the inverted graded generating function for the number of partitions in which no square parts are present

REFERENCES

Noureddine Chair, Partition Identities From Partial Supersymmetry, hep-th/0409011 2004.

J. A. Sellers, Journal of Integer Sequences, 7 (2004) Article 04.2.4

FORMULA

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

EXAMPLE

E.g."a(10)=8 because 10=8+2=7+3=6+4=5+3+2=6+2+2=4+2+2+2=2+2+2+2+2."

MAPLE

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

CROSSREFS

Sequence in context: A081360 A117409 A092833 * A179241 A157046 A017979

Adjacent sequences:  A100923 A100924 A100925 * A100927 A100928 A100929

KEYWORD

nonn

AUTHOR

Noureddine Chair (n.chair(AT)rocketmail.com), Nov 22 2004

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Last modified February 16 20:28 EST 2012. Contains 205962 sequences.