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%I #30 Apr 20 2023 10:24:32
%S 0,0,0,0,0,0,4,5,18,65,267,1238,6196,33480,187932,1095882,6629232
%N Number of twins of prime quadruples < 10^n.
%C Number of twins of prime quadruples with at most n digits. A twin of prime quadruples consists of two prime quadruples with a (minimal) distance of 30.
%H J. Brüggemann, <a href="http://ymmij.de/Nerd/p4/p4-2.pdf">The twins of prime quadruples up to 10^17</a> [71 MB]. [broken link]
%H J. Brüggemann, <a href="http://ymmij.de/Nerd/p4/calculation.pdf">Calculating prime quadruples, its twins, triples and quadruples</a>. [broken link]
%e For n=7 the a(7)=4 solutions are: [(1006301, 1006303, 1006307, 1006309), (1006331, 1006333, 1006337, 1006339)], [(2594951, 2594953, 2594957, 2594959), (2594981, 2594983, 2594987, 2594989)], [(3919211, 3919213, 3919217, 3919219), (3919241, 3919243, 3919247, 3919249)], [(9600551, 9600553, 9600557, 9600559), (9600581, 9600583, 9600587, 9600589)].
%Y Cf. A007530, A059925, A338868.
%K nonn,more
%O 1,7
%A _Hans H. Brüggemann_, Nov 13 2020
%E a(17) corrected by _Hans H. Brüggemann_, Apr 11 2021