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A057448 a(n+1) = next prime such that a(n+1)-1 | (a(1)...a(n))^5. 2

%I #4 Aug 10 2023 02:23:13

%S 2,3,5,7,11,13,17,19,23,29,31,37,41,43,47,53,59,61,67,71,73,79,83,89,

%T 97,101,103,107,109,113,127,131,137,139,149,151,157,163,167,173,179,

%U 181,191,197,199,211,223,227,229,233,239,241,251,263,269,271,277,281

%N a(n+1) = next prime such that a(n+1)-1 | (a(1)...a(n))^5.

%t NextPrime[ n_Integer ] := Module[ {k = n + 1}, While[ ! PrimeQ[ k ], k++ ]; Return[ k ] ]; f[ n_List ] := (a = n; b = Apply[ Times, a^5 ]; d = NextPrime[ a[[ -1 ]] ]; While[ ! IntegerQ[ b/(d - 1) ] && d < b+2, d = NextPrime[ d ] ]; AppendTo[ a, d ]; Return[ a ]); Nest[ f, {2}, 75 ]

%Y Cf. A007459 & A057447.

%K nonn

%O 1,1

%A _Robert G. Wilson v_, Sep 25 2000

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Last modified April 23 11:07 EDT 2024. Contains 371905 sequences. (Running on oeis4.)