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A213349
7-quantum transitions in systems of N >= 7 spin 1/2 particles, in columns by combination indices.
3
1, 16, 144, 9, 960, 180, 5280, 1980, 55, 25344, 15840, 1320, 109824, 102960, 17160, 286, 439296, 576576, 160160, 8008, 1647360, 2882880, 1201200, 120120, 1365, 5857280, 13178880, 7687680, 1281280, 43680, 19914752, 56010240
OFFSET
7,2
COMMENTS
For a general discussion, please see A213343.
This a(n) is for septuple-quantum transitions (q = 7).
It lists the flattened triangle T(7;N,k) with rows N = 7,8,... and columns k = 0..floor((N-7)/2).
REFERENCES
LINKS
Stanislav Sýkora, Magnetic Resonance on OEIS, Stan's NMR Blog (Dec 31, 2014), Retrieved Nov 12, 2019.
FORMULA
Set q = 7 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-7)/2)
7 | 1
8 | 16
9 | 144 9
10 | 960 180
11 | 5280 1980 55
MATHEMATICA
With[{q = 7}, 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 = 7
CROSSREFS
Cf. A051288 (q=0), A213343 to A213348 (q=1 to 6), A213350 to A213352 (q=8 to 10).
Cf. A054851 (first column), A004313 (row sums).
Sequence in context: A232311 A048533 A303145 * A336239 A332105 A032444
KEYWORD
nonn,tabf
AUTHOR
Stanislav Sykora, Jun 13 2012
STATUS
approved