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Revision History for A130078 (Bold, blue-underlined text is an addition; faded, red-underlined text is a deletion.)

Showing all changes.
Largest 2^x dividing A001623(n), the number of reduced three-line Latin rectangles.
(history; published version)
#7 by Joerg Arndt at Mon Oct 02 08:25:54 EDT 2017
STATUS

proposed

approved

#6 by Michel Marcus at Mon Oct 02 08:21:36 EDT 2017
STATUS

editing

proposed

#5 by Michel Marcus at Mon Oct 02 08:21:29 EDT 2017
FORMULA

a(n) = A006519(A001623(n)). - Michel Marcus, Oct 02 2017

PROG

(PARI) a001623(n) = n*(n-3)!*sum(i=0, n, sum(j=0, n-i, (-1)^j*binomial(3*i+j+2, j)<<(n-i-j)/(n-i-j)!)*i!);

a(n) = 2^valuation(a001623(n), 2); \\ Michel Marcus, Oct 02 2017

CROSSREFS
#4 by Michel Marcus at Mon Oct 02 08:12:12 EDT 2017
REFERENCES

John Riordan, A recurrence relation for three-line Latin rectangles, Amer. Math. Monthly, 59 (1952), pp. 159-162.

D. S. Stones, The many formulas for the number of Latin rectangles, Electron. J. Combin 17 (2010), A1.

D. S. Stones and I. M. Wanless, Divisors of the number of Latin rectangles, J. Combin. Theory Ser. A 117 (2010), 204-215.

LINKS

John Riordan, <a href="http://www.jstor.org/stable/2308187">A recurrence relation for three-line Latin rectangles</a>, Amer. Math. Monthly, 59 (1952), pp. 159-162.

D. S. Stones, <a href="http://www.combinatorics.org/ojs/index.php/eljc/article/view/v17i1a1/0">The many formulas for the number of Latin rectangles</a>, Electron. J. Combin 17 (2010), A1.

D. S. Stones and I. M. Wanless, <a href="http://dx.doi.org/10.1016/j.jcta.2009.03.019">Divisors of the number of Latin rectangles</a>, J. Combin. Theory Ser. A 117 (2010), 204-215.

STATUS

approved

editing

#3 by N. J. A. Sloane at Thu Jun 16 23:27:32 EDT 2016
REFERENCES

D. S. Stones, The many formulae formulas for the number of Latin rectangles, Electron. J. Combin 17 (2010), A1.

Discussion
Thu Jun 16
23:27
OEIS Server: https://oeis.org/edit/global/2523
#2 by N. J. A. Sloane at Fri Aug 27 03:00:00 EDT 2010
REFERENCES

D. S. Stones, The many formulae for the number of Latin rectangles, Electron. J. Combin 17 (2010), A1.

D. S. Stones and I. M. Wanless, Divisors of the number of Latin rectangles, J. Combin. Theory Ser. A 117 (2010), 204-215.

KEYWORD

nonn,new

nonn

#1 by N. J. A. Sloane at Fri May 11 03:00:00 EDT 2007
NAME

Largest 2^x dividing A001623(n), the number of reduced three-line Latin rectangles.

DATA

1, 4, 2, 8, 16, 64, 32, 64, 128, 512, 256, 2048, 8192, 16384, 4096, 65536, 32768, 131072, 65536, 262144, 524288, 2097152, 1048576, 2097152, 4194304, 16777216, 8388608, 134217728, 134217728, 1073741824, 134217728, 536870912, 2147483648

OFFSET

3,2

REFERENCES

John Riordan, A recurrence relation for three-line Latin rectangles, Amer. Math. Monthly, 59 (1952), pp. 159-162.

CROSSREFS
KEYWORD

nonn,new

AUTHOR

Douglas Stones (dssto1(AT)student.monash.edu.au), May 06 2007

STATUS

approved