Average of 4 primes where the integer Schwarzian derivative is zero.

Terms

a(0) =520a(1) =2397a(2) =3500a(3) =3518a(4) =3826a(5) =4439a(6) =4662a(7) =6620a(8) =7518a(9) =8926a(10) =9206a(11) =10220a(12) =10780a(13) =10938a(14) =12498a(15) =12640a(16) =12740a(17) =14049a(18) =14358a(19) =18623a(20) =20118a(21) =20262a(22) =22569a(23) =24419a(24) =25300a(25) =25706a(26) =26920a(27) =27498a(28) =28482a(29) =29500