%I #9 Feb 27 2020 23:13:38

%S 1,1,1,1,0,1,1,1,1,1,1,1,0,1,1,1,1,0,0,1,1,1,1,0,0,0,1,1,1,1,0,0,0,0,

%T 1,1,1,1,0,0,0,0,0,1,1,1,0,1,1,1,1,1,1,1,1,1,0,0,1,0,1,0,1,0,1,1,1,0,

%U 0,0,1,1,0,0,1,1,1,1,1,0,0,0,0,1,0,0,0,1,0,1,1,1,0,0,0,0,0,1,1,1,1,0,0,1,1

%N Gasket based on primes: take array read by diagonals from Gilbreath conjecture, omitting the initial row of primes (A036261) and replace all nonzero entries with 1's.

%D Lakhtakia, Akhlesh. "A simple gasket derived from prime numbers." Computers & graphics 13.1 (1989): 57-58.

%e The original array (before changing positive entries to 1's) is:

%e 1 2 2 4 2 4 2 4 6 2 6 4 2 4 6 6 2 6 4 2 6 4 6 8 4 2

%e 1 0 2 2 2 2 2 2 4 4 2 2 2 2 0 4 4 2 2 4 2 2 2 4 2 2

%e 1 2 0 0 0 0 0 2 0 2 0 0 0 2 4 0 2 0 2 2 0 0 2 2 0 0

%e 1 2 0 0 0 0 2 2 2 2 0 0 2 2 4 2 2 2 0 2 0 2 0 2 0 0

%e 1 2 0 0 0 2 0 0 0 2 0 2 0 2 2 0 0 2 2 2 2 2 2 2 0 8

%e 1 2 0 0 2 2 0 0 2 2 2 2 2 0 2 0 2 0 0 0 0 0 0 2 8 8

%e 1 2 0 2 0 2 0 2 0 0 0 0 2 2 2 2 2 0 0 0 0 0 2 6 0 8

%e 1 2 2 2 2 2 2 2 0 0 0 2 0 0 0 0 2 0 0 0 0 2 4 6 8 6

%e 1 0 0 0 0 0 0 2 0 0 2 2 0 0 0 2 2 0 0 0 2 2 2 2 2 4

%e ...

%Y Cf. A036261, A036262, A330548, A330549, A330551.

%K nonn,tabl

%O 1

%A _N. J. A. Sloane_, Dec 20 2019