login
This site is supported by donations to The OEIS Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
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 prime-difference [from A001223] which has prime-factor 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 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

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

EXAMPLE

18 is the 7th term:in first-6th ones {2,4,6,8,14,10} 3 does not occur with power 2 unlike in 18; 22 is the 8th term: in first-7th 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, A080374-A080376.

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

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified August 18 20:02 EDT 2019. Contains 326109 sequences. (Running on oeis4.)