OFFSET
0,2
COMMENTS
This modulo 15 of prime digit endings is important because it gives even odd prime types that appear in pairs: {1,4},{2,13},{7,8},{11,14}
FORMULA
b[n]={1, 2, 4, 7, 8, 11, 13, 14} T[n,m]=Mod[b[n]*b[m],15] a(n) = T[n,m]: antidiagonal form
EXAMPLE
Array looks like:
1, 2, 4, 7, 8, 11, 13, 14
2, 4, 8, 14, 1, 7, 11, 13
4, 8, 1, 13, 2, 14, 7, 11
7, 14, 13, 4, 11, 2, 1, 8
8, 1, 2, 11, 4, 13, 14, 7
11, 7, 14, 2, 13, 1, 8, 4
13, 11, 7, 1, 14, 8, 4, 2
14, 13, 11, 8, 7, 4, 2, 1
MATHEMATICA
Table[Mod[Prime[n], 15], {n, 1, 50}] a = {1, 2, 4, 7, 8, 11, 13, 14} b = Table[Mod[a[[n]]*a[[m]], 15], {n, 1, 8}, {m, 1, 8}] c = Table[Table[b[[n, l - n]], {n, 1, l - 1}], {l, 1, Dimensions[b][[1]] + 1}] Flatten[c]
CROSSREFS
KEYWORD
nonn,tabf,fini
AUTHOR
Roger L. Bagula, Jun 23 2006
STATUS
approved