login
This site is supported by donations to The OEIS Foundation.
Logo

Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A141715 Matrix square of triangle T = A141712, where the n-th diagonal of T equals the BINOMIAL transform of the (n-1)-th diagonal of T^2. 3
1, 2, 1, 6, 4, 1, 26, 20, 8, 1, 162, 136, 68, 16, 1, 1454, 1292, 732, 236, 32, 1, 18854, 17400, 10648, 4036, 836, 64, 1, 354258, 335404, 215708, 90152, 22692, 3020, 128, 1, 9671546, 9317288, 6192440, 2752332, 780400, 129556, 11108, 256, 1, 384587782 (list; table; graph; refs; listen; history; internal format)
OFFSET

0,2

EXAMPLE

This triangle, T^2, begins:

1;

2, 1;

6, 4, 1;

26, 20, 8, 1;

162, 136, 68, 16, 1;

1454, 1292, 732, 236, 32, 1;

18854, 17400, 10648, 4036, 836, 64, 1;

354258, 335404, 215708, 90152, 22692, 3020, 128, 1;

9671546, 9317288, 6192440, 2752332, 780400, 129556, 11108, 256, 1; ...

Triangle T=A141712 begins:

1;

1, 1;

2, 2, 1;

6, 6, 4, 1;

26, 26, 18, 8, 1;

162, 162, 114, 54, 16, 1;

1454, 1454, 1030, 506, 162, 32, 1;

18854, 18854, 13394, 6666, 2274, 486, 64, 1; ...

where the BINOMIAL transform of diagonal 2 of T^2:

BINOMIAL[6,20,68,236,836,3020,11108,41516,...]

equals: [6,26,114,506,2274,10346,47634,221786,...]

which is diagonal 3 of T.

PROG

(PARI) {T(n, k)=local(M, M2); if(n==k, 1, if(n==k+1, 2^n, M=matrix(n+1, n+1, r, c, if(r==c, 1, if(r>=c, sum(j=0, c-1, binomial(c-1, j)*T(r-c+j-1, j)) ))); (M^2)[n+1, k+1]))}

CROSSREFS

Cf. A141712 (T), A141713 (column 0), A141716 (column 1).

Sequence in context: A112356 A135885 A162312 * A098697 A193094 A021466

Adjacent sequences:  A141712 A141713 A141714 * A141716 A141717 A141718

KEYWORD

nonn,tabl

AUTHOR

Paul D. Hanna (pauldhanna(AT)juno.com), Jul 01 2008

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Transforms | Puzzles | Hot | Classics
Recent Additions | More pages | Superseeker | Maintained by The OEIS Foundation Inc.

Content is available under The OEIS End-User License Agreement .

Last modified February 17 16:49 EST 2012. Contains 206058 sequences.