OFFSET
1,1
COMMENTS
Quadratic analog of A117330 Determinants of 3 X 3 matrices of continuous blocks of 9 consecutive primes. See also: A001248 Squares of primes. The terminology "continuous" is used to distinguish from "discrete" which would be block 1: 4, 9, 25, 49, 121, 169, 289, 361, 529; block 2: 841, 961, 1369, 1681, 1849, 2209, 2809, 3481, 3721; and so forth.
EXAMPLE
a(1) = -213720 =
| 4 9 25|
| 49 121 169|
|289 361 529|.
a(2) =
| 9 25 49|
| 121 169 289|
| 361 529 841|.
MAPLE
a:= n-> LinearAlgebra[Determinant](Matrix(3, (i, j)-> ithprime(n+3*i-4+j)^2)):
seq(a(n), n=1..25); # Alois P. Heinz, Jan 25 2021
MATHEMATICA
m = 24; p = Prime[Range[m + 8]]^2; Table[Det @ Partition[p[[n ;; n + 8]], 3], {n, 1, m}] (* Amiram Eldar, Jan 25 2021 *)
PROG
(PARI) a(n) = matdet(matrix(3, 3, i, j, prime((n+j-1)+3*(i-1))^2)); \\ Michel Marcus, Jan 25 2021
CROSSREFS
KEYWORD
easy,sign
AUTHOR
Jonathan Vos Post, May 24 2006
EXTENSIONS
Wrong Formula and data corrected by Michel Marcus, Jan 25 2021
STATUS
approved