A359849
a(n) is the smallest tetranacci number (A000078) with exactly n distinct prime factors.
Original entry on oeis.org
1, 2, 15, 1490, 39648, 28074040, 100808458960497, 9966792788887776, 4997150614173857218560, 1835682610171974487231869, 889487735339682550112673527109223032, 52499930084496170026238596234557616056408988199026780675759699719704592
Offset: 0
a(4) = 39648, because 39648 is a tetranacci number with 4 distinct prime factors {2, 3, 7, 59} and this is the smallest such number.
A359850
a(n) is the index of the smallest tribonacci number (A000073) with exactly n distinct prime factors.
Original entry on oeis.org
2, 4, 8, 13, 20, 29, 49, 56, 101, 93, 124, 268, 221
Offset: 0
A359876
a(n) is the smallest tribonacci number (A000073) with exactly n prime factors (counted with multiplicity).
Original entry on oeis.org
1, 2, 4, 44, 24, 5768, 504, 10562230626642, 3136, 7046319384, 615693474, 53798080, 4680045560037375, 35574238430251050319992, 4659412488735286161146176, 23523635785731871586396890786299881280, 79932289960699059086717998848
Offset: 0
a(5) = 5768, because 5768 is a tribonacci number with 5 prime factors (counted with multiplicity) {2, 2, 2, 7, 103} and this is the smallest such number.
A359852
a(n) is the smallest Fibonacci n-step number with exactly n distinct prime factors.
Original entry on oeis.org
21, 504, 39648, 6930, 12669125245488, 471771076278370, 32818036405994618064, 71577732779401085355729600, 204945946670840805166309694624676331385919836360545974559162291811394735721440
Offset: 2
a(3) = 504, because 504 is a tribonacci number with 3 distinct prime factors {2, 3, 7} and this is the smallest such number.
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a(n) = my(v=vector(n+1), x=1, y=n+1); v[1]=v[y]=1; while(omega(v[x])!=n, y=x; x=x%(n+1)+1; v[x]=2*v[y]-v[x]); v[x]; \\ Jinyuan Wang, Jan 16 2023
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