A158893 Triangle read by rows: T(n,1)=7n-6; T(n,m)= 1+n-m, 1<m<=n.

1, 8, 1, 15, 2, 1, 22, 3, 2, 1, 29, 4, 3, 2, 1, 36, 5, 4, 3, 2, 1, 43, 6, 5, 4, 3, 2, 1, 50, 7, 6, 5, 4, 3, 2, 1, 57, 8, 7, 6, 5, 4, 3, 2, 1, 64, 9, 8, 7, 6, 5, 4, 3, 2, 1

Offset

1,2

References

H. S. M. Coxeter, Regular Polytopes, 3rd ed., Dover, NY, 1973, pp 159-162.

Links

Table of n, a(n) for n=1..55.

Formula

T(n,m)= ( T(n-1,m)*T(n,m-1)+1 )/T(n-1,m-1).

Row sums are n*(n+13)/2-6.

Example

{1},
{8, 1},
{15, 2, 1},
{22, 3, 2, 1},
{29, 4, 3, 2, 1},
{36, 5, 4, 3, 2, 1},
{43, 6, 5, 4, 3, 2, 1},
{50, 7, 6, 5, 4, 3, 2, 1},
{57, 8, 7, 6, 5, 4, 3, 2, 1},
{64, 9, 8, 7, 6, 5, 4, 3, 2, 1}

Mathematica

Clear[e, n, k];
e[n_, 0] := 7*n - 6;
e[n_, k_] := 0 /; k >= n;
e[n_, k_] := (e[n - 1, k]*e[n, k - 1] + 1)/e[n - 1, k - 1];
Table[Table[e[n, k], {k, 0, n - 1}], {n, 1, 10}];
Flatten[%]

Crossrefs

Sequence in context: A209684 A173988 A349123 * A342636 A332941 A107929

Adjacent sequences: A158890 A158891 A158892 * A158894 A158895 A158896

Keyword

nonn,tabl,easy

Author

Roger L. Bagula and Gary W. Adamson, Mar 29 2009

Extensions

Edited by the Associate Editors of the OEIS, Apr 22 2009

Status

approved