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A105160 A triangular array made from a negative permutation (intention to sum). 0
6, 4, 6, 14, 21, 35, 10, 15, 25, 35, 26, 39, 65, 91, 143, 22, 33, 55, 77, 121, 143, 38, 57, 95, 133, 209, 247, 323, 34, 51, 85, 119, 187, 221, 289, 323, 58, 87, 145, 203, 319, 377, 493, 551, 667, 46, 69, 115, 161, 253, 299, 391, 437, 529, 667, 74, 111, 185, 259, 407 (list; graph; refs; listen; history; internal format)
OFFSET

1,1

COMMENTS

Triangle begins ( modulo 3 plot has an chaotic design) {-6} {4, 6} {-14, -21, -35} {10, 15, 25, 35} {-26, -39, -65, -91, -143} {22, 33, 55, 77, 121, 143}

FORMULA

a(n) = if Mod[Prime[n], 2]=0 then Prime[n-1] else -Prime[n] T(n, k)=a(k)*Prime[n]

MATHEMATICA

a[1] = -Prime[2] a[n_] := a[n] = If[Mod[n, 2] == 0, Prime[n - 1], -Prime[n + 1]] digits = 25 aa = Table[Table[Prime[n]*a[m], {n, 1, m}], {m, 1, digits}] Flatten[Abs[aa]]

CROSSREFS

Sequence in context: A065445 A164293 A141796 * A200228 A021611 A011425

Adjacent sequences:  A105157 A105158 A105159 * A105161 A105162 A105163

KEYWORD

nonn,uned

AUTHOR

Roger Bagula (rlbagulatftn(AT)yahoo.com), Apr 10 2005

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Last modified February 16 19:43 EST 2012. Contains 205949 sequences.