The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 Please make a donation to keep the OEIS running. We are now in our 56th year. In the past year we added 10000 new sequences and reached almost 9000 citations (which often say "discovered thanks to the OEIS"). Other ways to donate

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A122560 Primes p such that p^2 is a sum of three successive primes, or primes in A076304. 4
 7, 11, 29, 31, 43, 151, 157, 191, 263, 311, 359, 367, 563, 823, 859, 881, 929, 997, 1013, 1019, 1021, 1087, 1297, 1471, 1613, 1733, 1787, 1913, 2153, 2161, 2203, 2293, 2411, 2473, 2543, 2549, 2557, 2579, 2689, 2731, 2971, 3209, 3253, 3299, 3779, 3881, 3923 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS A076304(n) are the Numbers n such that n^2 is a sum of three successive primes. LINKS Donovan Johnson and Charles R Greathouse IV, Table of n, a(n) for n = 1..10000 (first 1000 from Johnson) EXAMPLE A076304(n) begins {7,11,29,31,43,151,157,191,209,217,...}. So a(1) = 7 because A076304(1) = 7 is prime and 7^2 = 49 = 13 + 17 + 19 = p(6) + p(7) + p(8). MATHEMATICA Select[Table[Sqrt[Sum[Prime[k], {k, n, n + 2}]], {n, 400000}], PrimeQ] (* Ray Chandler, Sep 26 2006 *) PROG (PARI) has(n)=my(p=precprime(n\3), q=nextprime(n\3+1), r=n-p-q); if(r>q, r==nextprime(q+2), r==precprime(p-1) && r) list(lim)=my(v=List()); forprime(p=7, lim, if(has(p^2), listput(v, p))); Vec(v) \\ Charles R Greathouse IV, Jun 26 2019 CROSSREFS Cf. A076304. Sequence in context: A067006 A136020 A076304 * A136338 A193867 A110572 Adjacent sequences:  A122557 A122558 A122559 * A122561 A122562 A122563 KEYWORD nonn AUTHOR Alexander Adamchuk, Sep 20 2006 EXTENSIONS Extended by Ray Chandler, Sep 26 2006 Name edited by Zak Seidov, May 07 2014 STATUS approved

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

Last modified November 24 18:11 EST 2020. Contains 338616 sequences. (Running on oeis4.)