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 A064219 a(1) = 1; a(n) > 0; for each k from 1 to n, k divides a(n) or a(n)+1 and a(n) is the least such integer. 0
 1, 1, 2, 3, 15, 24, 35, 119, 504, 720, 2519, 2519, 41040, 83160, 83160, 196559, 524160, 524160, 3160079, 3160079, 3160079, 3160079, 68468400, 68468400, 68468400, 68468400, 4724319600, 4724319600, 26702675999, 26702675999 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,3 LINKS EXAMPLE a(5)=15 because (2 divides a(5)+1) and (3 divides a(5)) and (4 divides a(5)+1) and (5 divides a(5)). PROG (PARI) { a=1; for (n=1, 100, if (a%n && (a+1)%n, until (b, b=1; a++; for (k=1, n, if (a%k && (a+1)%k, b=0; break)))); write("b064219.txt", n, " ", a) ) } \\ Harry J. Smith, Sep 10 2009 CROSSREFS Sequence in context: A048613 A162890 A030072 * A244377 A244330 A060753 Adjacent sequences:  A064216 A064217 A064218 * A064220 A064221 A064222 KEYWORD easy,nonn AUTHOR Don Reble, Sep 21 2001 STATUS approved

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Last modified January 21 13:54 EST 2020. Contains 331113 sequences. (Running on oeis4.)