OFFSET
1,4
LINKS
Nathaniel Johnston, Table of n, a(n) for n = 1..10000
EXAMPLE
Triangle begins:
0
1 0 3
1 0 0 0 5
1 0 3 0 5 0 7
0 0 3 0 0 0 7 0 0
1 0 0 0 5 0 7 0 0 0 11
1 0 3 0 0 0 0 0 0 0 11 0 13
0 0 3 0 5 0 0 0 0 0 11 0 13 0 0
1 0 0 0 5 0 7 0 0 0 11 0 13 0 0 0 17
1 0 3 0 0 0 7 0 0 0 0 0 13 0 0 0 17 0 19
MAPLE
isnotcomp:=proc(n)return (n=1 or isprime(n)) end:
for n from 1 to 10 do for k from 1 to 2*n-1 do if(not k=n and (isnotcomp(k) and isnotcomp(2*n-k)))then print(k):else print(0):fi:od:od: # Nathaniel Johnston, Apr 18 2011
MATHEMATICA
T[n_, k_] := If[k != n && !CompositeQ[k] && !CompositeQ[2n - k], k, 0];
Table[T[n, k], {n, 1, 10}, {k, 1, 2n - 1}] // Flatten (* Jean-François Alcover, Dec 04 2017 *)
CROSSREFS
KEYWORD
easy,nonn,tabf
AUTHOR
Omar E. Pol, Jan 14 2009
STATUS
approved