Logo

Greetings from The On-Line Encyclopedia of Integer Sequences!

Hints

Search: id:A088427
Displaying 1-1 of 1 results found. page 1
     Format: long | short | internal | text      Sort: relevance | references | number      Highlight: on | off
A088427 Number of primes in arithmetic progression starting with 23 and with d=2n. +0
10
1, 1, 2, 2, 1, 1, 2, 1, 3, 2, 1, 3, 1, 1, 4, 1, 1, 2, 2, 1, 1, 2, 1, 2, 2, 1, 1, 2, 1, 2, 1, 1, 2, 1, 1, 1, 2, 1, 4, 2, 1, 3, 2, 1, 2, 1, 1, 1, 1, 1, 1, 2, 1, 4, 1, 1, 3, 2, 1, 1, 1, 1, 2, 2, 1, 1, 2, 1, 1, 2, 1, 3, 1, 1, 2, 1, 1, 2, 2, 1, 1, 1, 1, 3, 2, 1, 2, 2, 1, 1, 1, 1, 1, 2, 1, 1, 1, 1, 1, 2 (list; graph; listen)
OFFSET

1,3

COMMENT

Arithmetic progression is stopped when next term is not prime. E.g. for n=15 (d=30), a=3, that is 23,53,83,113 are prime, while next term, 143, is not prime.

MATHEMATICA

bb={}; Do[s=1; Do[If[PrimeQ[23+k*d], s=s+1, bb={bb, s}; Break[]], {k, 10}], {d, 2, 200, 2}]; Flatten[bb]

CROSSREFS

Cf. A088420, A088421, A088422, A088423, A088424, A088425, A088426, A088428, A088429.

Sequence in context: A116514 A124767 A112933 this_sequence A104482 A020945 A016429

Adjacent sequences: A088424 A088425 A088426 this_sequence A088428 A088429 A088430

KEYWORD

easy,nonn

AUTHOR

Zak Seidov (zakseidov(AT)yahoo.com), Sep 29 2003

page 1

Search completed in 0.002 seconds

Lookup | Welcome | Find friends | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Transforms | Puzzles | Hot | Classics
More pages | Superseeker | Maintained by N. J. A. Sloane (njas@research.att.com)

Last modified September 6 16:04 EDT 2008. Contains 143483 sequences.


AT&T Labs Research