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Smallest number of 1's to append to the binary representation of n such that primes become nonprimes and nonprimes become primes.
2

%I #5 Mar 30 2012 18:50:43

%S 1,5,2,2,4,1,1,1,1,2,3,3,1,1,1,2,1,1,1,1,1,4,2,3,2,1,3,4,2,1,1,2,1,2,

%T 1,1,1,3,1,2,3,7,1,1,3,4,1,1,2,1,1,2,2,1,2,1,3,12,1,3,1,2,1,4,1,5,1,1,

%U 1,2,1,7,1,1,1,2,2,1,1,3,1,2,2,5,6,1,23,4,6,1,2,3,3,2,1,1,1,1,1,10

%N Smallest number of 1's to append to the binary representation of n such that primes become nonprimes and nonprimes become primes.

%C n>1: a(n) = A063377(n) + A040081(n+1).

%Y Cf. A093009.

%K nonn

%O 1,2

%A _Reinhard Zumkeller_, Mar 14 2004