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A350095 a(n) is the smaller of 2 consecutive primes bounding an interval containing a record number A350097(n) of odd squarefree semiprimes (A046388).

%I A350095 #17 Mar 21 2024 08:36:39
%S A350095 13,31,89,199,211,887,1129,1327,9973,15683,19609,44293,155921,370261,
%T A350095 396733,492113,1357201,1671781,3826019,17836409,20831323,47465267,
%U A350095 107534587,122164747,434865437,436273009,2300942549,4302407359,10726904659,25056082087,42652618343
%N A350095 a(n) is the smaller of 2 consecutive primes bounding an interval containing a record number A350097(n) of odd squarefree semiprimes (A046388).
%H A350095 Lucas A. Brown, <a href="/A350095/b350095.txt">Table of n, a(n) for n = 1..32</a> (terms 1-28 from _Hugo Pfoertner_, 29-31 from _Martin Ehrenstein_)
%H A350095 Lucas A. Brown, <a href="https://github.com/lucasaugustus/oeis/blob/main/A350097.py">Python program</a>.
%F A350095 A350096(n) = nextprime(a(n)).
%e A350095 a(1) = 13: semiprime 15 < 17 = nextprime(a(1)) = A350096(1);
%e A350095 a(2) = 31: semiprimes 33, 35 < 37 = A350096(2);
%e A350095 a(6) = 887: semiprimes 889, 893, 895, 899, 901, 905 < 907 = A350096(6);
%e A350095 a(7) = 1129: semiprimes 1133, 1135, 1137, 1139, 1141, 1145, 1147, 1149 < 1151 = A350096(7);
%e A350095 a(8) = 1327: semiprimes 1329, 1333, 1337, 1339, 1343, 1345, 1347, 1349, 1351, 1355, 1357 < 1361 = A350096(8).
%Y A350095 A350096 are the upper ends of the intervals, A350097 are the corresponding counts of odd squarefree semiprimes in the intervals.
%Y A350095 Cf. A000101, A005250, A046388.
%K A350095 nonn
%O A350095 1,1
%A A350095 _Hugo Pfoertner_, Dec 25 2021
%E A350095 a(29)-a(31) from _Martin Ehrenstein_, Dec 28 2021
%E A350095 a(32) from _Lucas A. Brown_, Mar 21 2024