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a(n) is the smallest tribonacci number (A000073) with exactly n distinct prime factors.
4

%I #10 Jan 18 2023 02:21:41

%S 1,2,24,504,35890,8646064,1697490356184,120879712950776,

%T 98079530178586034536500564,748829299860308729347600,

%U 119816209721856219780831547518850,15418262617564622254988364568360573618470100684551892712710640455037970

%N a(n) is the smallest tribonacci number (A000073) with exactly n distinct prime factors.

%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/DistinctPrimeFactors.html">Distinct Prime Factors</a>

%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/TribonacciNumber.html">Tribonacci Number</a>

%e a(4) = 35890, because 35890 is a tribonacci number with 4 distinct prime factors {2, 5, 37, 97} and this is the smallest such number.

%Y Cf. A000073, A001221, A060319, A359849, A359850.

%K nonn

%O 0,2

%A _Ilya Gutkovskiy_, Jan 15 2023

%E a(11) from _Daniel Suteu_, Jan 17 2023