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%I #8 Aug 28 2022 11:39:03
%S 7,7,14,14,15,17,29,64,71,79,119,120,127,223,239,260,287,288,319,320,
%T 447,484,511,512,519,960,967,968,969,1044,1151,1152,1155,1156,1279,
%U 1280,1283,1387,1791,1792,1919,1920,1921,2048,2051,2052,2079,3872,3875,3876,3879,3880,4095,4096
%N a(n) = index in A354790 of first nonprime term divisible by prime(n).
%H N. J. A. Sloane, <a href="/A355897/b355897.txt">Table of n, a(n) for n = 1..236</a>
%e The first few nonprime terms in B = A354790, and their prime factors are:
%e n B(n)=p*q p pi(p) q pi(q)
%e 7, 6, 2, 1, 3, 2
%e 14, 35, 5, 3, 7, 4
%e 15, 22, 2, 1, 11, 5
%e 17, 39, 3, 2, 13, 6
%e 29, 85, 5, 3, 17, 7
%e 31, 14, 2, 1, 7, 4
%e 35, 33, 3, 2, 11, 5
%e B(14) = A354790(14) = 35 = 5*7 is the first nonprime term divisible by 5 = prime(3), therefore a(3) = 14.
%Y Cf. A354790, A354791, A354792.
%K nonn
%O 1,1
%A _N. J. A. Sloane_, Aug 28 2022
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