Integers k such that phi(prime(k)+1) = phi(prime(k)-1).

Terms

a(0) =3a(1) =5a(2) =20a(3) =156a(4) =254a(5) =377a(6) =593a(7) =1800a(8) =5903a(9) =5981a(10) =7925a(11) =18669a(12) =19240a(13) =41274a(14) =48296a(15) =135700a(16) =146866a(17) =228028a(18) =234303a(19) =251216a(20) =407377a(21) =654288a(22) =802222a(23) =886223a(24) =938654a(25) =1063412a(26) =1072766a(27) =1212140a(28) =1238668a(29) =1515063