OFFSET
1,5
COMMENTS
Conjecture: a(n) is nonzero for any n > 3.
LINKS
Zhi-Wei Sun, Table of n, a(n) for n = 1..300
EXAMPLE
a(1) = 0 since |1-1| = 0 is not a prime.
MATHEMATICA
a[n_]:=Det[Table[If[PrimeQ[Abs[i-j]]==True, 1, 0], {i, 1, n}, {j, 1, n}]]
Table[a[n], {n, 1, 50}]
CROSSREFS
KEYWORD
sign
AUTHOR
Zhi-Wei Sun, Aug 28 2013
STATUS
approved