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 A005250 Record gaps between primes. (Formerly M0994) 52
 1, 2, 4, 6, 8, 14, 18, 20, 22, 34, 36, 44, 52, 72, 86, 96, 112, 114, 118, 132, 148, 154, 180, 210, 220, 222, 234, 248, 250, 282, 288, 292, 320, 336, 354, 382, 384, 394, 456, 464, 468, 474, 486, 490, 500, 514, 516, 532, 534, 540, 582, 588, 602, 652 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS Here a "gap" means prime(n+1) - prime(n), but in other references it can mean prime(n+1) - prime(n) - 1. a(n+1)/a(n) <= 2, for all n <= 80, and a(n+1)/a(n) < 1 + f(n)/a(n) with f(n)/a(n) <= epsilon for some function f(n) and with 0 < epsilon <= 1. It also appears, with the small amount of data available, for all n <= 80, that a(n+1)/a(n) ~ 1. - John W. Nicholson, Jun 08 2014, updated Aug 05 2019 Equivalent to the above statement, A053695(n) = a(n+1) - a(n) <= a(n). - John W. Nicholson, Jan 20 2016 Conjecture: a(n) = O(n^2); specifically, a(n) <= n^2. - Alexei Kourbatov, Aug 05 2017 Conjecture: below the k-th prime, the number of maximal gaps is about 2*log(k), i.e., about twice as many as the expected number of records in a sequence of k i.i.d. random variables (see arXiv:1709.05508 for a heuristic explanation). - Alexei Kourbatov, Mar 16 2018 REFERENCES B. C. Berndt, Ramanujan's Notebooks Part IV, Springer-Verlag, see p. 133. R. K. Guy, Unsolved Problems in Number Theory, A8. N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence). LINKS Elizabeth Axoy, Table of n, a(n) for n = 1..80 (terms 1..75 from N. J. A. Sloane, 76..77 from John W. Nicholson) Jens Kruse Andersen, The Top-20 Prime Gaps Jens Kruse Andersen, New record prime gap Jens Kruse Andersen, Maximal gaps Alex Beveridge, Table giving known values of A000101(n), A005250(n), A107578(n) R. P. Brent, J. H. Osborn and W. D. Smith, Lower bounds on maximal determinants of +-1 matrices via the probabilistic method, arXiv preprint arXiv:1211.3248 [math.CO], 2012. C. K. Caldwell, Table of prime gaps C. K. Caldwell, Gaps up to 1132 R. K. Guy, Letter to N. J. A. Sloane, Aug 1986 R. K. Guy, Letter to N. J. A. Sloane, 1987 A. Kourbatov, Maximal gaps between prime k-tuples: a statistical approach, arXiv preprint arXiv:1301.2242 [math.NT], 2013 and J. Int. Seq. 16 (2013) #13.5.2. A. Kourbatov, Tables of record gaps between prime constellations, arXiv preprint arXiv:1309.4053 [math.NT], 2013. Alexei Kourbatov, The distribution of maximal prime gaps in Cramer's probabilistic model of primes, arXiv preprint arXiv:1401.6959 [math.NT], 2014. Alexei Kourbatov, Upper bounds for prime gaps related to Firoozbakht's conjecture, arXiv:1506.03042 [math.NT], 2015; and J. Int. Seq. 18 (2015) #15.11.2. A. Kourbatov, Verification of the Firoozbakht conjecture for primes up to four quintillion, arXiv:1503.01744 [math.NT], 2015; and Int. Math. Forum, 10 (2015), 283-288. Alexei Kourbatov, On the distribution of maximal gaps between primes in residue classes, arXiv preprint arXiv:1610.03340 [math.NT], 2016. Alexei Kourbatov, On the nth record gap between primes in an arithmetic progression, arXiv:1709.05508 [math.NT], 2017; and Int. Math. Forum, 13 (2018), 65-78. Alexei Kourbatov, Marek Wolf, Predicting maximal gaps in sets of primes, arXiv:1901.03785 [math.NT], 2019. T. R. Nicely, Some Results of Computational Research in Prime Numbers T. R. Nicely, List of Gaps Tomás Oliveira e Silva, Gaps between consecutive primes D. Shanks, On maximal gaps between successive primes, Mathematics of Computation, 18(88), 646-651. (1964). Matt Visser, Verifying the Firoozbakht, Nicholson, and Farhadian conjectures up to the 81st maximal prime gap, arXiv:1904.00499 [math.NT], 2019. Eric Weisstein's World of Mathematics, Prime Gaps Wikipedia, Prime gap Robert G. Wilson v, Notes (no date) Marek Wolf, A Note on the Andrica Conjecture, arXiv:1010.3945 [math.NT], 2010. J. Young and A. Potler, First occurrence prime gaps, Math. Comp., 52 (1989), 221-224. FORMULA a(n) = A000101(n) - A002386(n) = A008996(n-1) + 1. - M. F. Hasler, Dec 13 2007 a(n+1) = 1 + Sum_{i=1..n} A053695(i). - John W. Nicholson, Jan 20 2016 MATHEMATICA nn=10^7; Module[{d=Differences[Prime[Range[nn]]], ls={1}}, Table[If[d[[n]]> Last[ls], AppendTo[ls, d[[n]]]], {n, nn-1}]; ls] (* Harvey P. Dale, Jul 23 2012 *) PROG (PARI) p=q=2; g=0; until( g<(q=nextprime(1+p=q))-p & print1(g=q-p, ", "), ) \\ M. F. Hasler, Dec 13 2007 (PARI) p=2; g=0; m=g; forprime(q=3, 10^13, g=q-p; if(g>m, print(g", ", p, ", ", q); m=g); p=q) \\ John W. Nicholson, Dec 18 2016 (Haskell) a005250 n = a005250_list !! (n-1) a005250_list = f 0 a001223_list    where f m (x:xs) = if x <= m then f m xs else x : f x xs -- Reinhard Zumkeller, Dec 12 2012 CROSSREFS Records in A001223. For positions of records see A005669. Cf. A000040, A002386, A000101, A008996, A058320, A107578. Sequence in context: A274170 A173144 A049015 * A162762 A156097 A288793 Adjacent sequences:  A005247 A005248 A005249 * A005251 A005252 A005253 KEYWORD nonn,nice AUTHOR N. J. A. Sloane, R. K. Guy, May 20 1991 EXTENSIONS More terms from Andreas Boerner (andreas.boerner(AT)altavista.net), Jul 11 2000 Additional comments from Frank Ellermann, Apr 20 2001 More terms from Robert G. Wilson v, Jan 03 2002, May 01 2006 STATUS approved

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Last modified October 23 16:46 EDT 2019. Contains 328373 sequences. (Running on oeis4.)