a(n) is the minimum integer k such that the smallest prime factor of the n-th Fermat number exceeds 2^(2^n - k).

A358684

a(n) is the minimum integer k such that the smallest prime factor of the n-th Fermat number exceeds 2^(2^n - k).

Terms

    a(0) =0a(1) =0a(2) =0a(3) =0a(4) =0a(5) =23a(6) =46a(7) =73a(8) =206a(9) =491a(10) =999a(11) =2030a(12) =4080a(13) =8151a(14) =16208a(15) =32738a(16) =65507a(17) =131028a(18) =262121a(19) =524252

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