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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.)