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 A248498 #17 Oct 22 2014 10:49:27 %S A248498 1,8,2,2,2,4,2,2,2,2,2,8,2,4,6,2,4,2,2,2,4,2,2,6,6,2,6,4,2,4,4,8,4,2, %T A248498 2,4,2,2,10,8,4,20,4,8,2,8,2,4,54,2,6,26,8,26,6,4,4,2,8,2,2,2,4,2,6,6, %U A248498 10,2,2,2,4,4,6,6,2,4,2,8,2,2,4,10,2,4,46 %N A248498 The smallest number of consecutive primes beginning with prime(n+1) added to prime(n) necessary to produce another prime. %C A248498 Records are a(1) = 1, a(2) = 8, a(39) = 10, a(42) = 20, a(49) = 54, a(110) = 56, a(160) = 94, a(3070) = 158, a(13528) = 204, a(34721) = 216, a(391862) = 222, a(448696) = 298, a(651511) = 348, a(9776339) = 382, .... Assuming the sequence exists for all n it is unbounded so there are infinitely many records. - _Charles R Greathouse IV_, Oct 21 2014 %H A248498 Charles R Greathouse IV, <a href="/A248498/b248498.txt">Table of n, a(n) for n = 1..10000</a> %e A248498 a(1)=1 because 2+3=5 which is prime (only 1 prime added to 2 to get a prime). %e A248498 a(2)=8 because 3+5+7+11+13+17+19+23+29=127 which is prime (8 consecutive primes added to 3), and all of the partial sums are composite. %o A248498 (PARI) a(n) = my(p = prime(n), q = nextprime(p+1), s = p+q, nb = 1); while (! isprime(s), p=q; q=nextprime(p+1); s += q; nb++); nb; \\ _Michel Marcus_, Oct 07 2014 %Y A248498 Cf. A000040, A071196. %K A248498 nonn,easy %O A248498 1,2 %A A248498 _Gil Broussard_, Oct 07 2014