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A122750 A pattern triangular array with three coefficient states:{-2,-1,1} Rules: States {1,-1} going to States{1,-2,1} States{1,-2} going to {1,-1,1} States{-2,1} going to {-1,1,-1}. 1
1, -1, 1, 1, -2, 1, -1, 1, -1, 1, 1, -2, 1, -2, 1, -1, 1, -1, 1, -1, 1, 1, -2, 1, -2, 1, -2, 1, -1, 1, -1, 1, -1, 1, -1, 1, 1, -2, 1, -2, 1, -2, 1, -2, 1, -1, 1, -1, 1, -1, 1, -1, 1, -1, 1, 1, -2, 1, -2, 1, -2, 1, -2, 1, -2, 1 (list; table; graph; refs; listen; history; internal format)
OFFSET

1,5

COMMENTS

The unsigned version is defined by t(n,m)=1 + Mod[n - m, 2]*Mod[m, 2]. - Roger L. Bagula (rlbagulatftn(AT)yahoo.com), Sep 06 2008

If the signs are omitted, the row sums are {1, 2, 4, 4, 7, 6, 10, 8, 13, 10, 16, ...}. - Roger L. Bagula (rlbagulatftn(AT)yahoo.com), Sep 06 2008

FORMULA

T(n, k) := If [Mod[n, 2] == 1, (-1)^(k + 1), (-1)^k*(1 + Mod[k, 2])]

EXAMPLE

1

-1, 1

1, -2, 1

-1, 1, -1, 1

1, -2, 1, -2, 1}

-1, 1,-1, 1, -1, 1

1, -2, 1, -2, 1, -2, 1

MATHEMATICA

T[n_, k_] := If [Mod[n, 2] == 1, (-1)^(k + 1), (-1)^k*(1 + Mod[k, 2])] a = Table[Table[T[n, k], {k, 0, n}], {n, 0, 10}]; Flatten[a]

For the unsigned version: t[n_, m_] = 1 + Mod[n - m, 2]*Mod[m, 2]; Table[Table[t[n, m], {m, 0, n}], {n, 0, 10}]; Flatten[%] - Roger L. Bagula (rlbagulatftn(AT)yahoo.com), Sep 06 2008

CROSSREFS

Cf. A122581, A122582, A122583.

Sequence in context: A178085 A176047 A078572 * A030421 A085021 A060209

Adjacent sequences:  A122747 A122748 A122749 * A122751 A122752 A122753

KEYWORD

sign,tabl,uned

AUTHOR

Roger Bagula (rlbagulatftn(AT)yahoo.com), Sep 21 2006, Sep 04 2008

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Last modified February 17 23:05 EST 2012. Contains 206085 sequences.