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 A137690 #6 May 13 2023 01:50:53 %S A137690 3,11,59,79,719,7919,55439,425039,5525519,19709529839,197095298399, %T A137690 999294451257532807016639,2823006824802530179822007999, %U A137690 2649530397357338361250749788962714016407928543999 %N A137690 Primes of the form A128646(k)-1 for some k (listed in A137689), where A128646 = denominators of partial sums of 1/(prime(i)-1). %C A137690 The next term is A128646(243)-1, which has 148 decimal digits. New terms should be added to A137689, not here. %o A137690 (PARI) A137689_v=[3,4,5,7,8,9,10,11,15,16,23,24,26,47,48,54,78,79,80,243]/*see there*/; %o A137690 vecsort(vector(#A137689_v,k,denominator(sum(i=1,A137689_v[k],1/(prime(i)-1)))/*i.e. %o A137690 A128646(A137689_v[k])*/-1),0,8) /* ...,8 removes duplicate entries in PARI > 2.4.1 */ %Y A137690 Cf. A128646, A137689-A137692, A092063. %K A137690 nonn %O A137690 1,1 %A A137690 _M. F. Hasler_, Feb 07 2008