Number of possible arrangements of numbers 1 to n*(n+1)/2 in a triangle of n rows so that each row and each diagonal is increasing or decreasing.
1, 6, 24, 180, 4212, 461064, 30269371
5 seqfan posts
Fri Jul 6 17:12:41 CEST 2012 [seqfan] Re: Filling a triangle with numbers
Fri Jul 6 17:07:31 CEST 2012 [seqfan] Re: Filling a triangle with numbers
Fri Jul 6 16:31:10 CEST 2012 [seqfan] Re: Filling a triangle with numbers
Fri Jul 6 16:18:28 CEST 2012 [seqfan] Re: Filling a triangle with numbers
Fri Jul 6 15:51:07 CEST 2012 [seqfan] Filling a triangle with numbers
Index of A-numbers in seqfan: by ascending order
by month
by frequency
by keyword
Links to OEIS content are included according to
The OEIS End-User License Agreement
.