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A158893 Triangle read by rows: T(n,1)=7n-6; T(n,m)= 1+n-m, 1<m<=n. 1
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 (list; table; graph; refs; listen; history; text; internal format)
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: A181762 A209684 A173988 * 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

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Last modified June 14 12:04 EDT 2021. Contains 345025 sequences. (Running on oeis4.)