OFFSET
0,3
COMMENTS
Column 2 of A268367.
LINKS
Alois P. Heinz, Table of n, a(n) for n = 0..425 (terms n = 1..25 from R. H. Hardin)
FORMULA
a(n) = 2^floor(n/2) * n!. - Joel B. Lewis, Aug 11 2016
a(2n) = A065140(n) for terms > a(1) - Terry D. Grant, May 28 2017
a(n) = A158867(n, n) for n > 0. - G. C. Greubel, Mar 08 2022
EXAMPLE
Some solutions for n=5
..3..1....1..3....4..0....0..4....0..4....4..0....4..0....4..0....2..2....1..3
..1..3....2..2....3..1....3..1....2..2....3..1....1..3....2..2....0..4....0..4
..0..4....0..4....0..4....2..2....1..3....1..3....0..4....1..3....3..1....4..0
..0..4....0..4....2..2....1..3....4..0....0..4....2..2....0..4....4..0....3..1
..2..2....3..1....1..3....0..4....1..3....2..2....1..3....3..1....3..1....2..2
MATHEMATICA
Table[2^Floor[n/2] n!, {n, 0, 25}] (* Michael De Vlieger, Aug 11 2016 *)
PROG
(Magma) [2^Floor(n/2)*Factorial(n): n in [0..25]]; // G. C. Greubel, Mar 08 2022
(Sage) [2^(n//2)*factorial(n) for n in (0..25)] # G. C. Greubel, Mar 08 2022
KEYWORD
nonn
AUTHOR
R. H. Hardin, Feb 03 2016
EXTENSIONS
Title clarified by Joel B. Lewis, Aug 11 2016
a(0)=1 prepended by Alois P. Heinz, May 27 2017
STATUS
approved