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

Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A138062 Prime number n, lesser of twin primes, isolated from neighboring primes by +- 6 (or more). 0
419, 521, 809, 1049, 1151, 1721, 1931, 1949, 2027, 2111, 2309, 2591, 2729, 2999, 3119, 3359, 3371, 3389, 3557 (list; graph; refs; listen; history; internal format)
OFFSET

1,1

EXAMPLE

419,421 = twin primes -- isolation +- 6 (or more)

419-2 = 417 (3*139) 421+2 = 423 (3*3*47)

419-4 = 415 (5*83) 421+4 = 425 (5*5*17)

419-6 = 413 (7*59) 421+6 = 427 (7*61)

MATHEMATICA

q=6; s=""; For[i=1, i<10^2*5, n=Prime[i]; m=n+2; If[PrimeQ[m], a=0; For[j=2, j<=q, If[PrimeQ[n-j]||PrimeQ[m+j], a=1; Break[]]; j=j+2]; If[a==0, s=s<>ToString[n]<>", "]]; i++ ]; Print[s]

CROSSREFS

Sequence in context: A172779 A056068 A202527 * A097233 A142281 A142733

Adjacent sequences:  A138059 A138060 A138061 * A138063 A138064 A138065

KEYWORD

nonn

AUTHOR

Vladimir Orlovsky (4vladimir(AT)gmail.com), May 02 2008

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Transforms | Puzzles | Hot | Classics
Recent Additions | More pages | Superseeker | Maintained by The OEIS Foundation Inc.

Content is available under The OEIS End-User License Agreement .

Last modified February 13 12:01 EST 2012. Contains 205469 sequences.