The OEIS mourns the passing of Jim Simons and is grateful to the Simons Foundation for its support of research in many branches of science, including the OEIS.
The OEIS is supported by the many generous donors to the OEIS Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A129388 Primes that are equal to the mean of 5 consecutive squares. 3
 11, 83, 227, 443, 1091, 1523, 2027, 3251, 6563, 9803, 11027, 12323, 13691, 15131, 21611, 29243, 47963, 50627, 56171, 59051, 62003, 65027, 74531, 88211, 91811, 95483, 103043, 119027, 123203, 131771, 136163, 140627, 149771, 173891, 178931 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS The sum of 5 consecutive squares starting with k^2 is equal to 5*(6 + 4*k + k^2) and the mean is (6 + 4*k + k^2) = (k+2)^2 + 2. Hence a(n)= A056899(n+2). LINKS Vincenzo Librandi, Table of n, a(n) for n = 1..1000 EXAMPLE 11 = (1^2 + ... + 5^2)/5; 83 = (7^2 + ... + 11^2)/5; 227 = (13^2 + ... + 17^2)/5. MATHEMATICA Select[Table[n^2 + 2 n + 3, {n, 1, 600}], PrimeQ] (* Vincenzo Librandi, Mar 22 2013 *) PROG (Magma) [a: n in [1..600] | IsPrime(a) where a is n^2 + 2*n + 3 ]; // Vincenzo Librandi, Mar 22 2013 (SageMath) A102305=[n^2+2*n+3 for n in range(1, 1001)] [n^2+2*n+3 for n in (1..600) if is_prime(A102305[n-1])] # G. C. Greubel, Feb 03 2024 CROSSREFS Cf. A056899, A067201, A102305, A129389. Sequence in context: A026871 A123367 A177142 * A030692 A294831 A055369 Adjacent sequences: A129385 A129386 A129387 * A129389 A129390 A129391 KEYWORD nonn,easy AUTHOR Zak Seidov, Apr 12 2007 STATUS approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

Last modified June 17 18:36 EDT 2024. Contains 373463 sequences. (Running on oeis4.)