Smallest k such that 3^^n is not congruent to 3^^(n-1) mod k, where 3^^n denotes the power tower 3^3^...^3 (in which 3 appears n times).

A246491

Smallest k such that 3^^n is not congruent to 3^^(n-1) mod k, where 3^^n denotes the power tower 3^3^...^3 (in which 3 appears n times).

Terms

    a(0) =3a(1) =5a(2) =11a(3) =23a(4) =47a(5) =283a(6) =719a(7) =1439a(8) =2879a(9) =34549a(10) =138197a(11) =1266767a(12) =14920303a(13) =36449279a(14) =377982107

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