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A168144 First differences of A168143 which are different from 1, incremented by 14. 0

%I

%S 19,23,31,47,79

%N First differences of A168143 which are different from 1, incremented by 14.

%C All terms of the sequence are primes greater than 17.

%C Are there more than 5 terms?

%H E. S. Rowland, <a href="https://cs.uwaterloo.ca/journals/JIS/VOL11/Rowland/rowland21.html">A natural prime-generating recurrence</a>, Journal of Integer Sequences, 11 (2008), Article 08.2.8.

%H V. Shevelev, <a href="https://arxiv.org/abs/0910.4676">An infinite set of generators of primes based on the Rowland idea and conjectures concerning twin primes</a>, arXiv:0910.4676 [math.NT], 2009.

%H V. Shevelev, <a href="https://arxiv.org/abs/0911.3491">Generalizations of the Rowland theorem</a>, arXiv:0911.3491 [math.NT], 2009-2010.

%t A168143[17] = 37;

%t A168143[n_] := A168143[n] = If[GCD[n, A168143[n - 1]] > 1 && FactorInteger[n][[1, 1]] > 17, 3 n - 14, A168143[n - 1] + 1]

%t DeleteCases[Differences[A168143 /@ Range[17, 100]], 1] + 14 (* _Eric Rowland_, Jan 27 2019 *)

%Y Cf. A168143, A167495, A167494, A167493, A167197, A167195, A167170, A167168, A106108, A132199, A167054, A167053, A166944, A166945, A116533, A163961, A163963, A084662, A084663, A134162, A135506, A135508, A118679, A120293.

%K nonn

%O 1,1

%A _Vladimir Shevelev_, Nov 19 2009

%E Corrected and edited by _Eric Rowland_, Jan 27 2019

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Last modified February 22 12:42 EST 2020. Contains 332136 sequences. (Running on oeis4.)