cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

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A135895 Triangle, read by rows, equal to R^2, the matrix square of R = A135894.

Original entry on oeis.org

1, 2, 1, 7, 6, 1, 34, 39, 10, 1, 215, 300, 95, 14, 1, 1698, 2741, 990, 175, 18, 1, 16220, 29380, 11635, 2296, 279, 22, 1, 182714, 363922, 154450, 32865, 4410, 407, 26, 1, 2378780, 5135894, 2302142, 517916, 74319, 7524, 559, 30, 1, 35219202, 81557270
Offset: 0

Views

Author

Paul D. Hanna, Dec 15 2007

Keywords

Comments

Triangle P = A135880 is defined by: column k of P^2 equals column 0 of P^(2k+2) such that column 0 of P^2 equals column 0 of P shift left.

Examples

			Triangle R^2 begins:
1;
2, 1;
7, 6, 1;
34, 39, 10, 1;
215, 300, 95, 14, 1;
1698, 2741, 990, 175, 18, 1;
16220, 29380, 11635, 2296, 279, 22, 1;
182714, 363922, 154450, 32865, 4410, 407, 26, 1;
2378780, 5135894, 2302142, 517916, 74319, 7524, 559, 30, 1;
35219202, 81557270, 38229214, 8980944, 1353522, 145805, 11830, 735, 34, 1;
where R = A135894 begins:
1;
1, 1;
2, 3, 1;
6, 12, 5, 1;
25, 63, 30, 7, 1;
138, 421, 220, 56, 9, 1;
970, 3472, 1945, 525, 90, 11, 1; ...
where column k of R = column 0 of P^(2k+1)
and P = A135880 begins:
1;
1, 1;
2, 2, 1;
6, 7, 3, 1;
25, 34, 15, 4, 1;
138, 215, 99, 26, 5, 1;
970, 1698, 814, 216, 40, 6, 1; ...
where column k of P equals column 0 of R^(k+1).

Crossrefs

Cf. A135882 (column 0), A135890 (column 1); A135894 (R), A135880 (P), A135888 (P^3), A135892 (P^5).

Programs

  • PARI
    {T(n,k)=local(P=Mat(1),R=Mat(1),PShR);if(n>0,for(i=0,n, PShR=matrix(#P,#P, r,c, if(r>=c,if(r==c,1,if(c==1,0,P[r-1,c-1]))));R=P*PShR; R=matrix(#P+1, #P+1, r,c, if(r>=c, if(r<#P+1,R[r,c], if(c==1,(P^2)[ #P,1],(P^(2*c-1))[r-c+1,1])))); P=matrix(#R, #R, r,c, if(r>=c, if(r<#R,P[r,c], (R^c)[r-c+1,1])))));(R^2)[n+1,k+1]}

Formula

Column k of R^2 = column 1 of P^(2k+1) for k>=0 where triangle P = A135880; column 0 of R^2 = column 1 of P; column 1 of R^2 = column 1 of P^3; column 2 of R^2 = column 1 of P^5.

A135896 Triangle, read by rows, equal to R^3, the matrix cube of R = A135894.

Original entry on oeis.org

1, 3, 1, 15, 9, 1, 99, 81, 15, 1, 814, 816, 195, 21, 1, 8057, 9366, 2625, 357, 27, 1, 93627, 122148, 38270, 6006, 567, 33, 1, 1252752, 1795481, 611525, 105910, 11439, 825, 39, 1, 19003467, 29478724, 10721093, 1996988, 236430, 19404, 1131, 45, 1, 322722064
Offset: 0

Views

Author

Paul D. Hanna, Dec 15 2007

Keywords

Comments

Triangle P = A135880 is defined by: column k of P^2 equals column 0 of P^(2k+2) such that column 0 of P^2 equals column 0 of P shift left.

Examples

			Triangle R^3 begins:
1;
3, 1;
15, 9, 1;
99, 81, 15, 1;
814, 816, 195, 21, 1;
8057, 9366, 2625, 357, 27, 1;
93627, 122148, 38270, 6006, 567, 33, 1;
1252752, 1795481, 611525, 105910, 11439, 825, 39, 1;
19003467, 29478724, 10721093, 1996988, 236430, 19404, 1131, 45, 1; ...
where R = A135894 begins:
1;
1, 1;
2, 3, 1;
6, 12, 5, 1;
25, 63, 30, 7, 1;
138, 421, 220, 56, 9, 1;
970, 3472, 1945, 525, 90, 11, 1; ...
where column k of R = column 0 of P^(2k+1)
and P = A135880 begins:
1;
1, 1;
2, 2, 1;
6, 7, 3, 1;
25, 34, 15, 4, 1;
138, 215, 99, 26, 5, 1;
970, 1698, 814, 216, 40, 6, 1; ...
where column k of P equals column 0 of R^(k+1).

Crossrefs

Cf. A135883 (column 0); A135894 (R), A135880 (P), A135888 (P^3), A135892 (P^5).

Programs

  • PARI
    {T(n,k)=local(P=Mat(1),R=Mat(1),PShR);if(n>0,for(i=0,n, PShR=matrix(#P,#P, r,c, if(r>=c,if(r==c,1,if(c==1,0,P[r-1,c-1]))));R=P*PShR; R=matrix(#P+1, #P+1, r,c, if(r>=c, if(r<#P+1,R[r,c], if(c==1,(P^2)[ #P,1],(P^(2*c-1))[r-c+1,1])))); P=matrix(#R, #R, r,c, if(r>=c, if(r<#R,P[r,c], (R^c)[r-c+1,1])))));(R^3)[n+1,k+1]}

Formula

Column k of R^3 = column 2 of P^(2k+1) for k>=0 where triangle P = A135880; column 0 of R^3 = column 2 of P; column 1 of R^3 = column 2 of P^3; column 2 of R^3 = column 2 of P^5.

A135897 Triangle, read by rows, equal to R^4, the matrix 4th power of R = A135894.

Original entry on oeis.org

1, 4, 1, 26, 12, 1, 216, 138, 20, 1, 2171, 1716, 330, 28, 1, 25628, 23647, 5440, 602, 36, 1, 348050, 362116, 94515, 12348, 954, 44, 1, 5352788, 6138746, 1761940, 258391, 23400, 1386, 52, 1, 92056223, 114543428, 35429974, 5662412, 572331, 39556, 1898
Offset: 0

Views

Author

Paul D. Hanna, Dec 15 2007

Keywords

Comments

Triangle P = A135880 is defined by: column k of P^2 equals column 0 of P^(2k+2) such that column 0 of P^2 equals column 0 of P shift left.

Examples

			Triangle R^4 begins:
1;
4, 1;
26, 12, 1;
216, 138, 20, 1;
2171, 1716, 330, 28, 1;
25628, 23647, 5440, 602, 36, 1;
348050, 362116, 94515, 12348, 954, 44, 1;
5352788, 6138746, 1761940, 258391, 23400, 1386, 52, 1; ...
where R = A135894 begins:
1;
1, 1;
2, 3, 1;
6, 12, 5, 1;
25, 63, 30, 7, 1;
138, 421, 220, 56, 9, 1;
970, 3472, 1945, 525, 90, 11, 1; ...
where column k of R = column 0 of P^(2k+1)
and P = A135880 begins:
1;
1, 1;
2, 2, 1;
6, 7, 3, 1;
25, 34, 15, 4, 1;
138, 215, 99, 26, 5, 1;
970, 1698, 814, 216, 40, 6, 1; ...
where column k of P equals column 0 of R^(k+1).

Crossrefs

Cf. A135884 (column 0); A135894 (R), A135880 (P), A135888 (P^3), A135892 (P^5).

Programs

  • PARI
    {T(n,k)=local(P=Mat(1),R=Mat(1),PShR);if(n>0,for(i=0,n, PShR=matrix(#P,#P, r,c, if(r>=c,if(r==c,1,if(c==1,0,P[r-1,c-1]))));R=P*PShR; R=matrix(#P+1, #P+1, r,c, if(r>=c, if(r<#P+1,R[r,c], if(c==1,(P^2)[ #P,1],(P^(2*c-1))[r-c+1,1])))); P=matrix(#R, #R, r,c, if(r>=c, if(r<#R,P[r,c], (R^c)[r-c+1,1])))));(R^4)[n+1,k+1]}

Formula

Column k of R^4 = column 3 of P^(2k+1) for k>=0 where triangle P = A135880; column 0 of R^4 = column 3 of P; column 1 of R^4 = column 3 of P^3; column 2 of R^4 = column 3 of P^5.
Previous Showing 21-23 of 23 results.

Started in 1964 by Neil J. A. Sloane | Maintained by The OEIS Foundation Inc.

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