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This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A355897 a(n) = index in A354790 of first nonprime term divisible by prime(n).

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