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 A080287 Successively larger gaps in Ulam numbers start at this Ulam number. 4
 1, 4, 8, 18, 38, 87, 114, 155, 282, 751, 949, 1257, 1553, 1858, 2178, 4800, 5384, 18796, 37562, 64420, 252719, 933709, 289738117, 332250401, 667752899, 699497052, 966290117, 224582902442, 319654121875, 418843012121, 802386465583 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS The gaps are in A080288. REFERENCES D. E. Knuth, The Art of Computer Programming, vol 4A, section 7.1.3, exercise 141. LINKS Philip Gibbs, Judson McCranie, The Ulam Numbers up to One Trillion, (2017). EXAMPLE 87 and 97 are successive Ulam numbers and this is the first gap of 10 or larger, so 87 is in the sequence. CROSSREFS Cf. A002858, A080288, A214603, A274522. Sequence in context: A190062 A228231 A175657 * A280155 A075310 A075797 Adjacent sequences:  A080284 A080285 A080286 * A080288 A080289 A080290 KEYWORD nonn,more,hard AUTHOR Jud McCranie, Feb 12 2003 EXTENSIONS Added a(23) found by Don Knuth - Jud McCranie, Aug 22 2008 a(24) on Feb 29 2012; a(25) on Jul 20 2012; and a(26) on Jul 24 2012 by Jud McCranie a(27) found by Philip Gibbs, Sep 02 2015 a(28) found by Philip Gibbs and Jud McCranie, Sep 09 2015 a(29)-a(31) found by Philip Gibbs, Oct 2017 Missing term a(23) added by Jud McCranie, Oct 27 2017 STATUS approved

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Last modified January 19 20:29 EST 2019. Contains 319310 sequences. (Running on oeis4.)