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"Binary potency" of n: length of shortest blocks of 0's inserted between the bits of n required to "dilute" it into a nonprime.
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%I #4 Mar 30 2012 17:38:10

%S 0,1,2,0,2,0,1,0,0,0,1,0,1,0,0,0,2,0,1,0,0,0,2,0,0,0,0,0,3,0,1,0,0,0,

%T 0,0,1,0,0,0,1,0,3,0,0,0,3,0,0,0,0,0,3,0,0,0,0,0,1,0,3,0,0,0,0,0,1,0,

%U 0,0,1,0,1,0,0,0,0,0,1,0,0,0,2,0,0,0,0,0,1,0,0,0,0,0,0,0,1,0,0,0,1,0,1,0,0

%N "Binary potency" of n: length of shortest blocks of 0's inserted between the bits of n required to "dilute" it into a nonprime.

%C Zero for all nonprime n. Note that the +2 dilution of 3 is not the +1 dilution of 5!

%e 3 = 11 -> 0101 = 5 -> 001001 = 9, so a(3) = 2; 5 = 101 -> 010001 = 17 -> 001000001 = 65, so a(5) = 2

%Y Cf. A000040, A064892, A064893.

%K base,easy,nonn

%O 1,3

%A _Marc LeBrun_, Oct 10 2001