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%I #30 Jul 09 2020 03:16:57
%S 1,3,3,3,1,3,3,5,5,1,3,7,1,1,13,5,9,5,3,5,9,3,11,3,3,1,5,5,5,1,13,1,
%T 13,9,3,7,5,5,3,9,9,5,5,3,3,7,7,5,1,5,5,1,9,5,5,3,11,1,5,1,3,7,7,7,5,
%U 7,3,3,9,1,1,1,13,1,13,1,19,7,7,5,13,5,7,11
%N Number of composites lying between successive pairs of primes, beginning with pair (3,5). Bisection of A046933.
%H Jinyuan Wang, <a href="/A256736/b256736.txt">Table of n, a(n) for n = 1..1000</a>
%e [3,5] contains 4, so a(1)=4.
%e [7,11] contains 8,9,10, so a(2)=3.
%e For the third term in the sequence, use prime pair [13,17]. There are three composites between 13 and 17, thus the third term = 3.
%t Table[Prime[n + 1] - Prime[n] - 1, {n, 2, 100, 2}] (* _Hartmut F. W. Hoft_, Apr 24 2015 *)
%o (PARI) a(n) = prime(2*n+1)-prime(2*n)-1; \\ _Jinyuan Wang_, Jul 09 2020
%Y Complement of A256737 in regards to forming A046933.
%K nonn
%O 1,2
%A _Peter Woodward_, Apr 09 2015
%E Corrected and extended by _Hartmut F. W. Hoft_, Apr 24 2015
%E More terms from _Robert G. Wilson v_, May 03 2015
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