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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

Table of n, a(n) for n=1..87.

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.)