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 A342443 #58 Dec 15 2024 20:16:31 %S A342443 5,97,991,9949,99971,999983,9999991,99999989,999999937,9999999943, %T A342443 99999999977,999999999989,9999999999763,99999999999959,999999999999989 %N A342443 a(n) is the largest prime < 10^n that is the sum of at least two consecutive primes. %C A342443 The minimum corresponding number of consecutive primes to get this largest prime a(n) is A342444(n) and the first prime of these A342444(n) consecutive primes is A342454(n). %C A342443 Differs from A342439 where the corresponding primes result of the longest sum < 10^n of consecutive primes. %C A342443 a(n) is the largest n-digit prime A003618(n) for n = 2, 6, 7, 8, 9, 11, 12, ... %C A342443 a(13) >= k = 10^13 - 237. If a(13) > k then it is the sum of at least 30000 primes. k can be written as the sum of 6449 consecutive primes. - _David A. Corneth_, Mar 13 2021 %C A342443 No sum of 30000 or more consecutive primes is in the interval [10^13 - 237, 10^13 - 1], so a(13) = 10^13 - 237. - _Jon E. Schoenfield_, Mar 14 2021 %F A342443 A342439(n) <= a(n) <= A003618(n). %e A342443 a(1) = 5 = 2 + 3, since it is not possible to obtain the greatest 1-digit prime 7 when adding consecutive primes. %e A342443 a(2) = 29 + 31 + 37 = 97, since (29, 31, 37) are consecutive primes and 97 is the largest 2-digit prime. %Y A342443 Cf. A003618, A050936, A067377, A342439, A342440, A342444, A342453, A342454. %K A342443 nonn,base,more %O A342443 1,1 %A A342443 _Bernard Schott_, Mar 12 2021 %E A342443 a(9) from _Jinyuan Wang_, Mar 13 2021 %E A342443 a(10) from _David A. Corneth_, Mar 13 2021 %E A342443 a(11)-a(12) from _Jinyuan Wang_, Mar 13 2021 %E A342443 a(13)-a(14) from _Jon E. Schoenfield_, Mar 13 2021 %E A342443 a(15) from _Max Alekseyev_, Dec 11 2024