Let a=a(n) be the minimum positive integer such that [a,a+n-1] does not contain any values of sigma(k) (i.e., sum of all positive divisors of k). According to http://www.mathlinks.ro/Forum/viewtopic.php?t=26906 the initial terms of a(n) are 2, 9, 49, 423, 1333 Would anybody like to extend and/or submit this sequence to OEIS? P.S. This sequence is related to A007369. Max