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 A228616 Determinant of the n X n matrix with (i,j)-entry equal to 1 or 0 according as 2*(i + j) - 1 is prime or not. 9
 1, 0, -1, -2, 0, 0, 0, -2, 3, 11, 24, -60, -16, 31, -217, -1148, -164, 132, 395, 697, -191, -76, 125664, -213885, -171654, 114902, 353497, -388325, -1738118, -222898, 248633, 382075, -1637075, 21100, 4049068, -189147708, -279083383, 472023163, -19063401, -6718578823 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,4 COMMENTS Conjecture: a(n) is nonzero for any n > 7. Clearly this conjecture implies that there are infinitely many primes. LINKS Zhi-Wei Sun, Table of n, a(n) for n = 1..250 EXAMPLE a(1) = 1 since 2*(1 + 1) - 1 = 3 is a prime. MATHEMATICA a[n_]:=a[n]=Det[Table[If[PrimeQ[2(i+j)-1], 1, 0], {i, 1, n}, {j, 1, n}]] Table[a[n], {n, 1, 40}] CROSSREFS Cf. A000040, A069191, A228615, A228591. Sequence in context: A063958 A126164 A145007 * A151670 A153587 A059286 Adjacent sequences:  A228613 A228614 A228615 * A228617 A228618 A228619 KEYWORD sign AUTHOR Zhi-Wei Sun, Aug 27 2013 STATUS approved

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Last modified October 23 01:57 EDT 2018. Contains 316518 sequences. (Running on oeis4.)