Numbers k such that 4^k == 2 (mod k).

Terms

a(0) =1a(1) =2a(2) =14a(3) =1022a(4) =20066a(5) =80519a(6) =107663a(7) =485918a(8) =1284113a(9) =1510313a(10) =2531678a(11) =3677198a(12) =3933023a(13) =4557713a(14) =8277458a(15) =8893262a(16) =21122318a(17) =24849833a(18) =26358638a(19) =39852014a(20) =42448478a(21) =71871113a(22) =76712318a(23) =80646143a(24) =98058097a(25) =104832833a(26) =106694033a(27) =131492498a(28) =144322478a(29) =146987033