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A282063
A(n, k) = k-th Wilson prime p of order n with p >= n and k running over the positive integers. Square array read by antidiagonals.
0
5, 13, 2, 563, 3, 7
OFFSET
1,1
COMMENTS
A Wilson prime of order n is a prime p such that (n-1)!*(p-n)!-(-1)^n == 0 (modulo p^2).
LINKS
Eric Weisstein's World of Mathematics, Wilson Prime
Wikipedia, Wilson prime
EXAMPLE
Array A(n, k) starts:
5, 13, 563
2, 3, 11, 107, 4931
7
10429
5, 7, 47
11
PROG
(PARI) is_wilson(n, order) = Mod((order-1)!*(n-order)!-(-1)^order, n^2)==0
table(rows, cols) = for(x=1, rows, my(i=0); forprime(p=x, , if(is_wilson(p, x), print1(p, ", "); i++; if(i==cols, print(""); break))))
table(4, 3) \\ print initial 4 rows and 3 columns of table
CROSSREFS
Cf. A007540 (row 1), A079853 (row 2), A152413 (row 17), A128666 (column 1).
Sequence in context: A073878 A164793 A065934 * A035412 A338985 A065865
KEYWORD
nonn,hard,tabl,more
AUTHOR
Felix Fröhlich, Feb 05 2017
STATUS
approved