The OEIS is supported by the many generous donors to the OEIS Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A130077 Largest x such that 2^x divides A001623(n), the number of reduced three-line Latin rectangles. 2
 0, 2, 1, 3, 4, 6, 5, 6, 7, 9, 8, 11, 13, 14, 12, 16, 15, 17, 16, 18, 19, 21, 20, 21, 22, 24, 23, 27, 27, 30, 27, 29, 31, 33, 32, 34, 35, 37, 36, 37, 38, 40, 39, 42, 44, 45, 43, 50, 46, 48, 47, 49, 50, 52, 51, 52, 53, 55, 54, 59, 58, 62, 58, 60, 63, 65, 64, 66, 67, 69, 68, 69, 70 (list; graph; refs; listen; history; text; internal format)
 OFFSET 3,2 LINKS 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. FORMULA a(n) = A007814(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) = valuation(a001623(n), 2); \\ Michel Marcus, Oct 02 2017 CROSSREFS Cf. A001623, A007814, A130078, A130079. Sequence in context: A029636 A293517 A122514 * A080412 A300948 A098164 Adjacent sequences:  A130074 A130075 A130076 * A130078 A130079 A130080 KEYWORD nonn AUTHOR Douglas Stones (dssto1(AT)student.monash.edu.au), May 06 2007 STATUS approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

Last modified January 28 07:25 EST 2022. Contains 350654 sequences. (Running on oeis4.)