login
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
OFFSET
1,1
EXAMPLE
Triangle begins:
10;
6, 9;
-4, -6, -10;
-14, -21, -35, -49;
22, 33, 55, 77, 121;
26, 39, 65, 91, 143, 169;
...
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
KEYWORD
nonn,uned
AUTHOR
Roger L. Bagula, Apr 10 2005
STATUS
approved