

A080377


Each a(n) is a difference of suitable consecutive primes, a(n)=Prime[1+A080376(n)]Prime[A080376(n)]. a(n+1) is the smallest primedifference [from A001223] which has primefactor not present in previous terms or was present but at lower power.


0



2, 4, 6, 8, 14, 10, 18, 22, 34, 16, 26, 32, 38, 50, 62, 54, 58, 46, 64, 86, 82, 74, 98, 106, 94, 118, 122, 128, 146, 134, 142, 162, 178, 158
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OFFSET

1,1


LINKS

Table of n, a(n) for n=1..34.


EXAMPLE

18 is the 7th term:in first6th ones {2,4,6,8,14,10} 3 does not occur with power 2 unlike in 18; 22 is the 8th term: in first7th terms 11 is not a prime factor unlike 22. several even numbers do not arise in this sequence, e.g.:12,20,36,48, etc..


MATHEMATICA

s=1; Do[s1=s; s=LCM[s, d=Prime[n+1]Prime[n]]; If[Greater[s, s1], Print[d]], {n, 1, 10000000}]


CROSSREFS

Cf. A001223, A080374A080376.
Sequence in context: A072791 A058320 A014320 * A086526 A086529 A054409
Adjacent sequences: A080374 A080375 A080376 * A080378 A080379 A080380


KEYWORD

nonn


AUTHOR

Labos Elemer, Feb 27 2003


STATUS

approved



