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 A187222 Gullwing primes: primes in the gullwing sequence A187220. 2
 3, 7, 23, 31, 47, 71, 191, 311, 367, 503, 607, 967, 1303, 1367, 1439, 1471, 1663, 1871, 2399, 4951, 5471, 5623, 6263, 9431, 10103, 10271, 10687, 12119, 12511, 14431, 14879, 15647, 21871, 22111, 22271, 22807, 23039, 24223, 24919 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS Nathaniel Johnston, Table of n, a(n) for n = 1..3406 David Applegate, Omar E. Pol and N. J. A. Sloane, The Toothpick Sequence and Other Sequences from Cellular Automata N. J. A. Sloane, Catalog of Toothpick and Cellular Automata Sequences in the OEIS FORMULA A000040 INTERSECT A187220. MATHEMATICA m = 200 (* number of gullwing terms *); s = (2*(x/((1-x)*(1 + 2*x))))*(1 + 2*x*Product[1 + x^(2^k-1) + 2*x^2^k, {k, 0, Ceiling[Log[2, m]]}]) + O[x]^(m-1); Select[CoefficientList[s, x] + 1, PrimeQ] (* Jean-François Alcover, Jul 23 2017 *) CROSSREFS Cf. A000040, A139253, A187220. Sequence in context: A127781 A271918 A165580 * A122094 A260350 A270384 Adjacent sequences:  A187219 A187220 A187221 * A187223 A187224 A187225 KEYWORD nonn AUTHOR Omar E. Pol, Mar 09 2011, Mar 10 2011 EXTENSIONS More terms from Nathaniel Johnston, Mar 22 2011 STATUS approved

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Last modified November 15 15:59 EST 2018. Contains 317239 sequences. (Running on oeis4.)