Logo

Greetings from The On-Line Encyclopedia of Integer Sequences!

Hints

Search: id:A088422
Displaying 1-1 of 1 results found. page 1
     Format: long | short | internal | text      Sort: relevance | references | number      Highlight: on | off
A088422 Number of primes in arithmetic progression starting with 7 and with d=2n. +0
10
1, 2, 3, 1, 2, 4, 1, 2, 1, 1, 2, 2, 1, 1, 6, 1, 2, 3, 1, 2, 1, 1, 2, 1, 1, 2, 2, 1, 1, 3, 1, 2, 3, 1, 1, 4, 1, 2, 1, 1, 2, 1, 1, 1, 2, 1, 2, 3, 1, 2, 4, 1, 2, 1, 1, 1, 1, 1, 1, 2, 1, 2, 1, 1, 2, 3, 1, 1, 1, 1, 2, 2, 1, 1, 7, 1, 1, 2, 1, 2, 1, 1, 2, 1, 1, 2, 2, 1, 1, 1, 1, 2, 3, 1, 2, 2, 1, 1, 1, 1, 1, 2, 1, 1, 1 (list; graph; listen)
OFFSET

1,2

COMMENT

Arithmetic progression is stopped when next term is not prime. E.g. for n=3, a=3, that is 7,13,19 are prime, while next term, 25, is not prime.

MATHEMATICA

bb={}; Do[s=1; Do[If[PrimeQ[7+k*d], s=s+1, bb={bb, s}; Break[]], {k, 10}], {d, 2, 200, 2}]; Flatten[bb]

CROSSREFS

Cf. A088420, A088421, A088423, A088424, A088425, A088426, A088427, A088428, A088429.

Sequence in context: A167157 A081514 A109206 this_sequence A100833 A097293 A026793

Adjacent sequences: A088419 A088420 A088421 this_sequence A088423 A088424 A088425

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 November 24 23:16 EST 2009. Contains 167481 sequences.


AT&T Labs Research