A155897 - OEIS

%I #6 Apr 20 2013 04:52:39

%S 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,

%T 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,

%U 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

%N Square matrix T(m,n)=1 if (2m+1)^n-2 is prime, 0 otherwise; read by antidiagonals.

%C 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.

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

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

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

%K easy,nonn,tabl

%O 1,1

%A _M. F. Hasler_, Feb 01 2009