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%I #6 Oct 30 2024 15:33:45
%S 3,8,15,33,63,132,260,528,1057,2123,4236,8464,16932,33860,67732,
%T 135453,270927,541836,1083716,2167408,4334796,8669604,17339208,
%U 34678448,69356872,138713720,277427448,554854896,1109709804,2219419612,4438839324,8877678536,17755357084,35510714180,71021428384,142042856736
%N Length of n-th region in A376198.
%C We define a region in A376198 to consist of a maximal string of non-prime terms followed by a string of prime terms.
%F Apart from the initial 3, this is the first differences of A376752.
%F This is also, very approximately, the sum of A376763 and a subsequence of A063124.
%e The first two regions in A376198 consist of terms 1 to 3 (of length a(1) = 3) and terms 4 to 11 (of length a(2) = 8).
%Y Cf. A063124, A376198, A376752, A376763.
%K nonn
%O 1,1
%A _N. J. A. Sloane_, Oct 30 2024