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A105156 The sum of a triangular array made from a negative 6-fold permutation product (. 0
10, 15, 20, 119, 308, 533, 986, 1463, 2300, 3741, 4960, 7289, 9758, 12083, 15416, 20193, 25960, 30561, 38056, 45369, 51976, 62489, 72542, 85707, 102820, 117261, 130192, 146697, 161320, 180009, 218440, 242481, 272356, 295653, 339124, 366477 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Triangle begins:

   10;

    6,   9;

   -4,  -6, -10;

  -14, -21, -35, -49;

   22,  33,  55,  77, 121;

   26,  39,  65,  91, 143, 169;

  ...

LINKS

Table of n, a(n) for n=1..36.

MATHEMATICA

a[n_] := -Prime[n] /; 10 - Mod[Prime[n], 10] == 1;

a[n_] := -Prime[n] /; 10 - Mod[Prime[n], 10] == 3;

a[n_] := Prime[ n] /; (10 - Mod[Prime[n], 10] == 7) || (10 - Mod[Prime[n], 10] == 9);

a[1] = 5; a[3] = -2;

digits = 200

aa = Table[Abs[Apply[Plus, Table[Prime[n]*a[m], {n, 1.m}]]], {m, 1, digits}]

CROSSREFS

Cf. A105155.

Sequence in context: A091418 A055986 A045161 * A108614 A336548 A115708

Adjacent sequences:  A105153 A105154 A105155 * A105157 A105158 A105159

KEYWORD

nonn,uned

AUTHOR

Roger L. Bagula, Apr 10 2005

STATUS

approved

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Last modified July 25 18:32 EDT 2021. Contains 346291 sequences. (Running on oeis4.)