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A144432 Triangle read by rows: m=-1; A(n,k) := (m*n - m*k + 1)A(n - 1, k - 1) + (m*k - (m - 1))A(n - 1, k); t(n,m)=A(n,m)^2-A(n,m)-1. 0
-1, -1, -1, -1, -1, -1, -1, 1, 1, -1, -1, 5, 1, 5, -1, -1, 11, 1, 1, 11, -1, -1, 19, 41, 71, 41, 19, -1, -1, 29, 71, 29, 29, 71, 29, -1, -1, 41, 239, 701, 869, 701, 239, 41, -1, -1, 55, 379, 811, 181, 181, 811, 379, 55, -1 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,12

COMMENTS

Row sums are:{-1, -2, -3, 0, 9, 22, 189, 256, 2829, 2850}.

LINKS

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

FORMULA

m=-1; A(n,k) := (m*n - m*k + 1)A(n - 1, k - 1) + (m*k - (m - 1))A(n - 1, k); t(n,m)=A(n,m)^2-A(n,m)-1.

EXAMPLE

{-1},

{-1, -1},

{-1, -1, -1},

{-1, 1, 1, -1},

{-1, 5, 1, 5, -1},

{-1, 11, 1, 1, 11, -1},

{-1, 19, 41, 71, 41, 19, -1},

{-1, 29, 71, 29, 29, 71, 29, -1},

{-1, 41, 239,701, 869, 701, 239, 41, -1},

{-1, 55, 379, 811, 181, 181, 811, 379, 55, -1}

MATHEMATICA

m=-1; A[n_, 1] := 1; A[n_, n_] := 1; A[n_, k_] := (m*n - m*k + 1)A[n - 1, k - 1] + (m*k - (m - 1))A[n - 1, k]; a = Table[A[n, k], {n, 10}, {k, n}]; Table[Table[a[[n]][[m]]^2 - a[[n]][[m]] - 1, {m, 1, n}], {n, 1, Length[a]}]; Flatten[%]

CROSSREFS

Cf. A098593.

Sequence in context: A094882 A019840 A205109 * A010686 A021070 A176260

Adjacent sequences:  A144429 A144430 A144431 * A144433 A144434 A144435

KEYWORD

uned,sign,tabl

AUTHOR

Roger L. Bagula, Oct 04 2008

STATUS

approved

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Last modified June 6 11:14 EDT 2020. Contains 334827 sequences. (Running on oeis4.)