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 A120805 Primes with consecutive digits. 2
 2, 3, 5, 7, 23, 43, 67, 89, 109, 4567, 10987, 76543, 78901, 678901, 23456789, 45678901, 9012345678901, 789012345678901, 56789012345678901234567890123, 90123456789012345678901234567, 10987654321098765432109876543210987 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Digits can be in ascending or descending order. After 9 comes 0 or after 0 comes 1. The number of primes with n consecutive digits: 4,4,1,1,3,1,0,2,0,0,0,0,1,0,1,0,0,0,0,0,0,0,0,0,0,0,0,0,2,0,0,0,0,0,1,1,0,0,0,0,0,0,1,0,0,0,0,0,0,0,...,. LINKS MATHEMATICA f[n_] := Block[{u = Range@n, d = Reverse@ Range@n, t = Table[1, {n}]}, Select[ Drop[ Union@ Flatten@ Table[ FromDigits /@ Mod[{u, d} + {i*t, i*t}, 10], {i, 10}], 2], PrimeQ@# &]]; Array[f, 35] // Flatten CROSSREFS Cf. A000040, A118697; union of A006055 & A120804. Sequence in context: A048398 A059170 A068710 * A177119 A096265 A356271 Adjacent sequences: A120802 A120803 A120804 * A120806 A120807 A120808 KEYWORD nonn,base AUTHOR Robert G. Wilson v, Jul 05 2006 STATUS approved

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Last modified January 31 04:27 EST 2023. Contains 359947 sequences. (Running on oeis4.)