p = 3n+1时,p + 14 = 3n + 15 =3 (n+5),不是质数
p = 3n+2时,p + 10 = 3n + 12 =3 (n+4),不是质数
p = 3n时,只有当n = 1时,p = 3是质数,同时p + 10 = 13,p + 14 = 17都是质数
所以p只有一个,等于3
p = 3n+1时,p + 14 = 3n + 15 =3 (n+5),不是质数
p = 3n+2时,p + 10 = 3n + 12 =3 (n+4),不是质数
p = 3n时,只有当n = 1时,p = 3是质数,同时p + 10 = 13,p + 14 = 17都是质数
所以p只有一个,等于3