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A133529
Sum of squares of three consecutive primes.
32
38, 83, 195, 339, 579, 819, 1179, 1731, 2331, 3171, 4011, 4899, 5739, 6867, 8499, 10011, 11691, 13251, 14859, 16611, 18459, 21051, 24219, 27531, 30219, 32259, 33939, 36099, 40779, 46059, 52059, 55251, 60291, 64323, 69651, 74019, 79107, 84387, 89859, 94731, 101283
OFFSET
1,1
COMMENTS
It is easy to see that all terms > 83 are divisible by 3.
Likewise all terms except 38 are congruent to 3 (mod 8). - Franklin T. Adams-Watters, Jun 17 2015
LINKS
FORMULA
a(n) = A069484(n) + A001248(n+2). - Michel Marcus, Nov 08 2013
EXAMPLE
a(1)=38 because 2^2 + 3^2 + 5^2 = 38.
MATHEMATICA
a = 2; Table[Prime[n]^a + Prime[n + 1]^a + Prime[n + 2]^a, {n, 1, 100}]
Total/@Partition[Prime[Range[50]]^2, 3, 1] (* Vincenzo Librandi, Jun 18 2015 *)
PROG
(PARI) for( n= 1, 100, k= sum(i=n, n+2, prime(i)^2) ; print1(k, ", ")) \\ K. D. Bajpai, Jun 17 2015
(Magma) [&+[ NthPrime(n+i)^2 : i in [0..2]] : n in [1..20]]; // K. D. Bajpai, Jun 17 2015
CROSSREFS
KEYWORD
nonn
AUTHOR
Artur Jasinski, Sep 14 2007
EXTENSIONS
a(38)-a(41) from K. D. Bajpai, Jun 18 2015
STATUS
approved