|
Search: id:A075893
|
|
|
| A075893 |
|
Average of three successive primes squared, (prime(n)^2+prime(n+1)^2+prime(n+2)^2)/3, n>=3. |
|
+0
4
|
|
| 65, 113, 193, 273, 393, 577, 777, 1057, 1337, 1633, 1913, 2289, 2833, 3337, 3897, 4417, 4953, 5537, 6153, 7017, 8073, 9177, 10073, 10753, 11313, 12033, 13593, 15353, 17353, 18417, 20097, 21441, 23217, 24673, 26369, 28129, 29953, 31577, 33761
(list; graph; listen)
|
|
|
OFFSET
|
3,1
|
|
|
COMMENT
|
Unlike the average of three successive primes, the average of three successive primes (greater than 3) squared is always integral.
A133529(n)/3, n >= 3. - Artur Jasinski (grafix(AT)csl.pl), Sep 30 2007
|
|
FORMULA
|
(prime(n)^2+prime(n+1)^2+prime(n+2)^2)/3, n>=3.
|
|
EXAMPLE
|
a(3)=65 because (prime(3)^2+prime(4)^2+prime(5)^2)/3=(5^2+7^2+11^2)/3=65.
|
|
MATHEMATICA
|
b = {}; a = 2; Do[k = (Prime[n]^a + Prime[n + 1]^a + Prime[n + 2]^a)/3; AppendTo[b, k], {n, 3, 50}]; b - Artur Jasinski (grafix(AT)csl.pl), Sep 30 2007
|
|
CROSSREFS
|
Cf. A133529, A084951, A133940.
Sequence in context: A094447 A020224 A063519 this_sequence A064901 A039482 A118159
Adjacent sequences: A075890 A075891 A075892 this_sequence A075894 A075895 A075896
|
|
KEYWORD
|
easy,nonn
|
|
AUTHOR
|
Zak Seidov (zakseidov(AT)yahoo.com), Oct 17 2002
|
|
EXTENSIONS
|
Edited by N. J. A. Sloane (njas(AT)research.att.com), Jun 30 2008 at the suggestion of R. J. Mathar
|
|
|
Search completed in 0.002 seconds
|
