0,5

An eigentriangle of triangle T may be defined by taking the termwise product of row n-1 of T and the first n terms of the eigensequence of T; 0<=k<=n.

Row sums = A125812 shifted 1 place to the left: (1, 2, 6, 28, 204,...).

Sum of n-th row terms = rightmost term of (n+1)-th row.

1, 1;

1, 3, 1;

1, 7, 7, 1;

1, 15, 35, 15, 1;

... (and the eigensequence of A022166 = A125812: (1, 1, 2, 6, 28, 204,...) we apply the termwise product of (n-1)-th row of A022166 and the first n terms of A125812.

First few rows of the triangle = 1;

1, 1;

1, 3, 2;

1, 7, 14, 6;

1, 15, 70, 90, 28;

1, 31, 310, 930, 868, 204;

... Example: row 3 of A02166 = (1, 7, 7, 1), first 4 terms of A143774 = (1, 1, 2, 6), so row 3 of A143774 = (1*1, 7*1, 7*2, 1*6) = (1, 7, 14, 6).

Given triangle A022166: 1;

A022166, Cf. A125812

Sequence in context: A163626 A028246 A082038 this_sequence A158474 A090452 A110439

Adjacent sequences: A143771 A143772 A143773 this_sequence A143775 A143776 A143777

nonn,tabf

Gary W. Adamson (qntmpkt(AT)yahoo.com), Aug 31 2008