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%I #5 Jun 16 2017 22:22:09
%S 1,2311,4621,331,2641,4951,121,2431,4741,451,2761,31,2341,4651,361,
%T 2671,4981,151,2461,4771,481,2791,61,2371,4681,391,2701,5011,181,2491,
%U 4801,511,2821,91,2401,4711,421,2731,5041,211,2521,4831,541,2851,5161,871,3181
%N Lexicographically earliest sequence of distinct positive terms such that the absolute difference of two consecutive terms has at least 5 distinct prime factors.
%C Conjecturally: this sequence is a permutation of the natural numbers, and a(n) ~ n.
%C This sequence is related to A280659: here we consider the absolute difference, there the sum, of consecutive terms.
%H Rémy Sigrist, <a href="/A288798/b288798.txt">Table of n, a(n) for n = 1..25000</a>
%H Rémy Sigrist, <a href="/A288798/a288798.gp.txt">PARI program for A288798</a>
%e The first terms, alongside the primes p dividing |a(n) - a(n+1)|, are:
%e n a(n) p
%e -- ---- --------------
%e 1 1 2, 3, 5, 7, 11
%e 2 2311 2, 3, 5, 7, 11
%e 3 4621 2, 3, 5, 11, 13
%e 4 331 2, 3, 5, 7, 11
%e 5 2641 2, 3, 5, 7, 11
%e 6 4951 2, 3, 5, 7, 23
%e 7 121 2, 3, 5, 7, 11
%e 8 2431 2, 3, 5, 7, 11
%e 9 4741 2, 3, 5, 11, 13
%e 10 451 2, 3, 5, 7, 11
%e 11 2761 2, 3, 5, 7, 13
%e 12 31 2, 3, 5, 7, 11
%e 13 2341 2, 3, 5, 7, 11
%e 14 4651 2, 3, 5, 11, 13
%e 15 361 2, 3, 5, 7, 11
%e 16 2671 2, 3, 5, 7, 11
%e 17 4981 2, 3, 5, 7, 23
%e 18 151 2, 3, 5, 7, 11
%e 19 2461 2, 3, 5, 7, 11
%e 20 4771 2, 3, 5, 11, 13
%Y Cf. A280659.
%K nonn
%O 1,2
%A _Rémy Sigrist_, Jun 16 2017