Let t(x) be the highest power of 2 which divides x+1. Then a(1)=3; a(n) is the least prime p for which t(p) > t(a(n-1)).

A084924

Let t(x) be the highest power of 2 which divides x+1. Then a(1)=3; a(n) is the least prime p for which t(p) > t(a(n-1)).

Terms

    a(0) =3a(1) =7a(2) =31a(3) =127a(4) =1279a(5) =3583a(6) =5119a(7) =6143a(8) =8191a(9) =81919a(10) =131071a(11) =524287a(12) =14680063a(13) =109051903a(14) =654311423a(15) =738197503a(16) =2147483647a(17) =21474836479a(18) =51539607551a(19) =824633720831

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