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.
%I A037070 #19 Jul 21 2025 06:09:44
%S A037070 1,8,46,303,5133,17984,216816,1270607,41146179,420243162,2524038155,
%T A037070 36159205628,343392568900,1955010428258,15237833654620,
%U A037070 260219446617109,2621513397605657,24619309639366177,233874804775621799,684559920583084690,20920441130654929928,200085344903558463823
%N A037070 a(n)-th prime is the smallest prime containing exactly n 9's.
%H A037070 Andrew R. Booker, <a href="https://t5k.org/nthprime/">The Nth Prime Page</a>.
%H A037070 Kim Walisch, <a href="https://github.com/kimwalisch/primecount">primecount</a>, Fast prime counting function library.
%F A037070 a(n) = A000720(A037071(n)). - _Amiram Eldar_, Jul 21 2025
%t A037070 (* see A037071 for f *) PrimePi[ Table[ f[n, 9], {n, 1, 13}]]
%Y A037070 Cf. A000720, A037071, A034388.
%Y A037070 Cf. A037052, A037054, A037056, A037058, A037060, A037062, A037064, A037066, A037068.
%K A037070 nonn,base,hard
%O A037070 0,2
%A A037070 _Patrick De Geest_, Jan 04 1999
%E A037070 One more term from _Vladeta Jovovic_, Jan 10 2002
%E A037070 a(0)=1 prepended by _Sean A. Irvine_, Dec 06 2020
%E A037070 a(14)-a(21) calculated using Kim Walisch's primecount and added by _Amiram Eldar_, Jul 21 2025