Primes p of the form 3k+1 such that sum_{x=1..p} cos(2*Pi*x^3/p) < -sqrt(p).

Terms

a(0) =97a(1) =139a(2) =151a(3) =199a(4) =211a(5) =331a(6) =433a(7) =541a(8) =547a(9) =601a(10) =607a(11) =631a(12) =751a(13) =787a(14) =937a(15) =1039a(16) =1063a(17) =1249a(18) =1321a(19) =1327a(20) =1381a(21) =1471a(22) =1483a(23) =1663a(24) =1693a(25) =1741a(26) =1747a(27) =1879a(28) =1999a(29) =2113