Sum of 2^k for all residues k found in the Fibonacci sequence mod n.

Terms

a(0) =1a(1) =3a(2) =7a(3) =15a(4) =31a(5) =63a(6) =127a(7) =175a(8) =511a(9) =1023a(10) =1327a(11) =4031a(12) =7471a(13) =16383a(14) =32767a(15) =43951a(16) =127807a(17) =238895a(18) =502063a(19) =1048575a(20) =1319215a(21) =2719023a(22) =7798639a(23) =10692015a(24) =33554431a(25) =61209903a(26) =134217727a(27) =259173375a(28) =337649967a(29) =1073741823