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 A309367 The number of lucky numbers between two consecutive primes, bounds excluded. 1
 0, 0, 0, 1, 0, 1, 0, 1, 1, 0, 1, 0, 0, 0, 2, 0, 0, 1, 1, 0, 1, 0, 1, 1, 1, 0, 1, 0, 1, 1, 1, 2, 0, 1, 0, 0, 1, 0, 2, 0, 0, 1, 0, 1, 0, 2, 1, 0, 0, 1, 2, 0, 0, 0, 2, 1, 0, 1, 0, 0, 2, 2, 0, 0, 0, 3, 0, 1, 0, 0, 1, 1, 0, 0, 0, 1, 2, 1, 0, 1, 0, 2, 0, 0, 0, 0, 1 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,15 LINKS EXAMPLE a(1) = 0 because between the first two primes (2,3) are no lucky numbers. a(4) = 1 because between 7 and 1 is one lucky number (9). a(15) = 2 because between 47 and 53 are two lucky numbers (49, 51). MAPLE # uses[A000959List] A309367List := proc(mx) local L, j; L := convert(A000959List(ithprime(mx)), set): j := n -> {seq(k, k = [\$ithprime(n)+1..ithprime(n+1)-1])}: seq(nops(j(n) intersect L), n = 1..mx) end: A309367List(87); # Peter Luschny, Mar 27 2020 PROG (Sage) # uses[lucky from A000959] def lucky_range(a, b):     return [l for l in lucky(b) if a <= l < b] P = prime_range(250) [len(lucky_range(P[i]+1, P[i+1])) for i in range(len(P)-1)] CROSSREFS Cf. A000040, A000959, A309365. Sequence in context: A275947 A337976 A125005 * A122179 A335877 A125203 Adjacent sequences:  A309364 A309365 A309366 * A309368 A309369 A309370 KEYWORD nonn AUTHOR Hauke Löffler, Jul 25 2019 STATUS approved

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Last modified May 10 04:54 EDT 2021. Contains 343748 sequences. (Running on oeis4.)