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A084239 Rank of K-groups of Furstenberg transformation group C*-algebras of n-torus. 2
1, 2, 3, 4, 6, 8, 13, 20, 32, 52, 90, 152, 268, 472, 845, 1520, 2766, 5044, 9277, 17112, 31724, 59008, 110162, 206260, 387282, 729096, 1375654, 2601640, 4929378, 9358944, 17797100, 33904324, 64678112, 123580884, 236413054, 452902072 (list; graph; refs; listen; history; internal format)
OFFSET

0,2

REFERENCES

K. Reihani, C*-algebras from Anzai flows and their K-groups, preprint, 2003.

K. Reihani, K-theory of Furstenberg transformation group C^*-algebras, Arxiv preprint arXiv:1109.4473, 2011

FORMULA

a(n) = constant term of prod(i=1, n, 1+t^(i-.5(n+1))) for odd n and a(n) = constant term of (1+t^(.5))*prod(i=1, n, 1+t^(i-.5(n+1))) for even n.

Sums of antidiagonals of A067059, i.e. a(n) is sum over k of number of partitions of [k(n-k)/2] into up to k parts each no more than n-k. Close to 2^(n+1)*sqrt(6/(pi*n^3)) and seems to be even closer to something like 2^(n+1)*sqrt(6/(pi*(n^3+0.9*n^2-0.1825*n+1.5))). - Henry Bottomley (se16(AT)btinternet.com), Jul 20 2003

CROSSREFS

Cf. A000980.

Sequence in context: A000029 A155051 A018137 * A049708 A000031 A111023

Adjacent sequences:  A084236 A084237 A084238 * A084240 A084241 A084242

KEYWORD

nonn

AUTHOR

Kamran Reihani (reyhan_k(AT)modares.ac.ir), Jun 21 2003

EXTENSIONS

More terms from Henry Bottomley (se16(AT)btinternet.com), Jul 20 2003

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Last modified February 16 09:27 EST 2012. Contains 205904 sequences.