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%I #17 Dec 17 2023 11:28:09
%S 0,1,1,1,5,5,1,5,1,3,5,5,3,3,3,3,1,1,5,5,1,1,1,11,1,5,9,5,1,3,9,3,3,5,
%T 1,5,5,3,7,7,1,1,3,7,1,11,3,3,11,17,9,5,5,5,1,5,1,9,3,5,11,5,9,9,5,3,
%U 5,7,13,11,9,3,9,3,3,3,3,3,9,3,5,3,5,5,3,1,1,9,9,5,3,3,5,5,21
%N Number of composites lying between successive pairs of primes, beginning with pair (2,3). Bisection of A046933.
%e For the third term in the sequence, use prime pair (11,13). Only composite that lies between is "12", thus the third value in the sequence is "1".
%t Flatten[Differences/@Partition[Prime[Range[200]],2]]-1 (* _Harvey P. Dale_, Dec 17 2023 *)
%o (PARI) a(n)=my(q=prime(2*n)); q-precprime(q-1)-1 \\ _Charles R Greathouse IV_, Apr 21 2015
%Y Complement of A256736 with respect to A046933.
%K nonn
%O 1,5
%A _Peter Woodward_, Apr 09 2015
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