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A155897 Square matrix T(m,n)=1 if (2m+1)^n-2 is prime, 0 otherwise; read by antidiagonals. 1
0, 1, 1, 0, 1, 1, 1, 0, 1, 1, 1, 0, 0, 1, 0, 1, 0, 1, 1, 0, 1, 0, 0, 0, 0, 0, 1, 1, 0, 0, 0, 0, 1, 0, 1, 0, 1, 0, 1, 0, 0, 1, 1, 0, 1, 0, 0, 1, 0, 1, 1, 0, 0, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 1, 1, 0, 1, 0, 0, 0, 0, 0, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0 (list; graph; refs; listen; history; internal format)
OFFSET

1,1

COMMENTS

In some sense a "minimal" possible generalization of the pattern of Mersenne primes (cf. A000043) is to consider powers of odd numbers (> 1) minus 2. Since even powers obviously correspond to an odd power of the base squared, it is sufficient to consider only odd powers, cf. A155899.

PROG

(PARI) T = matrix( 19, 19, m, n, isprime((2*m+1)^n-2)) ;

A155897 = concat( vector( vecmin( matsize(T)), i, vector( i, j, T[j, i-j+1])))

CROSSREFS

Cf. A084714, A128472, A094786, A014224, A109080, A090669, A128455, A128457, A128458, A128459, A128460, A128461.

Sequence in context: A157658 A123506 A051105 * A144610 A181632 A105565

Adjacent sequences:  A155894 A155895 A155896 * A155898 A155899 A155900

KEYWORD

easy,nonn

AUTHOR

M. F. Hasler (www.univ-ag.fr/~mhasler), Feb 01 2009

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Last modified February 15 12:59 EST 2012. Contains 205788 sequences.