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

Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A133940 Numbers n such that one-third of the sum of squares of three consecutive primes is prime (A084951). 3
4, 5, 8, 13, 15, 26, 46, 47, 50, 55, 57, 59, 61, 65, 66, 69, 77, 82, 89, 91, 94, 101, 105, 116, 134, 136, 137, 138, 144, 157, 194 (list; graph; refs; listen; history; internal format)
OFFSET

1,1

COMMENTS

With exception of the two first term all numbers in A133529 are divisible by 3

EXAMPLE

a(1)=4 because (Prime[4]^2 + Prime[5]^2 + Prime[6]^2)/3=113 is prime

MATHEMATICA

b = {}; a = 2; Do[k = (Prime[n]^a + Prime[n + 1]^a + Prime[n + 2]^a)/3; If[PrimeQ[k], AppendTo[b, n]], {n, 1, 200}]; b

CROSSREFS

Cf. A133529, A133940.

Sequence in context: A027975 A011980 A061765 * A174398 A030978 A101948

Adjacent sequences:  A133937 A133938 A133939 * A133941 A133942 A133943

KEYWORD

nonn

AUTHOR

Artur Jasinski (grafix(AT)csl.pl), Sep 30 2007

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 15 23:53 EST 2012. Contains 205860 sequences.