Primes p such that (p-1)/2 and (p+1)/2 have same sum of divisors.

Terms

a(0) =29a(1) =2729a(2) =29683a(3) =37747a(4) =73133a(5) =149837a(6) =159667a(7) =168269a(8) =185371a(9) =244147a(10) =695477a(11) =880027a(12) =891749a(13) =910747a(14) =1088669a(15) =1298309a(16) =1371991a(17) =1479113a(18) =2414717a(19) =3531329a(20) =6593729a(21) =7452019a(22) =9590311a(23) =13542811a(24) =14527889a(25) =15592877a(26) =18718939a(27) =25650533