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A309334 Lucky prime gaps: differences between consecutive lucky primes. 3
4, 6, 18, 6, 6, 24, 6, 6, 48, 24, 12, 30, 18, 12, 18, 42, 24, 24, 18, 18, 42, 12, 12, 30, 24, 54, 36, 24, 12, 6, 12, 12, 30, 54, 12, 30, 18, 36, 60, 54, 54, 6, 12, 12, 18, 48, 6, 24, 6, 78, 30, 18, 42, 12, 156, 12, 72, 24, 12, 18, 66, 30, 30, 54, 24, 30, 48, 54 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Since (except for 3) all lucky primes == 1 (mod 6), a(n) >= 6 for n >= 2. - Robert Israel, Jul 26 2019

LINKS

Robert Israel, Table of n, a(n) for n = 1..10000

FORMULA

a(n) = A031157(n+1) - A031157(n).

EXAMPLE

a(1) = 4 because difference between the first (3) and second (7) lucky prime is 4.

a(2) = 6 because difference between 7 and 13 is 6.

MAPLE

N:= 10^4: # for lucky primes up to 2*N+1

L:= [seq(2*i+1, i=0..N)]:

for n from 2 while n < nops(L) do

  r:= L[n];

  L:= subsop(seq(r*i=NULL, i=1..nops(L)/r), L);

od:

LP:= select(isprime, L):

LP[2..-1]-LP[1..-2]; # Robert Israel, Jul 26 2019

PROG

(SageMath)

[A031157[i+1]-A031157[i] for i in range(100)]

CROSSREFS

Cf. A031157, A001223, A309333.

Sequence in context: A061361 A332986 A113610 * A263319 A062046 A102020

Adjacent sequences:  A309331 A309332 A309333 * A309335 A309336 A309337

KEYWORD

nonn

AUTHOR

Hauke Löffler, Jul 24 2019

STATUS

approved

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Last modified May 27 13:15 EDT 2020. Contains 334657 sequences. (Running on oeis4.)