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A213351
9-quantum transitions in systems of N >= 9 spin 1/2 particles, in columns by combination indices.
3
1, 20, 220, 11, 1760, 264, 11440, 3432, 78, 64064, 32032, 2184, 320320, 240240, 32760, 455, 1464320, 1537536, 349440, 14560, 6223360, 8712704, 2970240, 247520, 2380, 24893440, 44808192, 21385728, 2970240, 85680, 94595072, 212838912, 135442944, 28217280
OFFSET
9,2
COMMENTS
For a general discussion, please see A213343.
This a(n) is for nonuple-quantum transitions (q = 9).
It lists the flattened triangle T(9;N,k) with rows N = 9,10,... and columns k = floor((N-9)/2).
REFERENCES
LINKS
Stanislav Sýkora, Magnetic Resonance on OEIS, Stan's NMR Blog (Dec 31, 2014), Retrieved Nov 12, 2019.
FORMULA
Set q = 9 in: T(q;N,k) = 2^(N-q-2*k)*binomial(N,k)*binomial(N-k,q+k).
EXAMPLE
Starting rows of the triangle:
N | k = 0, 1, ..., floor((N-9)/2)
---+------------------------------
9 | 1
10 | 20
11 | 220 11
12 | 1760 264
13 | 11440 3432 78
MATHEMATICA
With[{q = 9}, Table[2^(n - q - 2 k)*Binomial[n, k] Binomial[n - k, q + k], {n, q, q + 10}, {k, 0, Floor[(n - q)/2]}]] // Flatten (* Michael De Vlieger, Nov 20 2019 *)
PROG
(PARI) See A213343; set thisq = 9
CROSSREFS
Cf. A051288 (q=0), A213343 to A213350 (q=1 to 8), A213352 (q= 10).
Cf. A140354 (first column,with offset 9), A004315 (row sums).
Sequence in context: A141790 A229575 A125408 * A140236 A341371 A004411
KEYWORD
nonn,tabl
AUTHOR
Stanislav Sykora, Jun 13 2012
STATUS
approved