A359848
a(n) is the smallest tribonacci number (A000073) with exactly n distinct prime factors.
Original entry on oeis.org
1, 2, 24, 504, 35890, 8646064, 1697490356184, 120879712950776, 98079530178586034536500564, 748829299860308729347600, 119816209721856219780831547518850, 15418262617564622254988364568360573618470100684551892712710640455037970
Offset: 0
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.
A359851
a(n) is the index of the smallest tetranacci number (A000078) with exactly n distinct prime factors.
Original entry on oeis.org
3, 5, 8, 15, 20, 30, 53, 60, 80, 89, 130, 252
Offset: 0
A359877
a(n) is the smallest tetranacci number (A000078) with exactly n prime factors (counted with multiplicity).
Original entry on oeis.org
1, 2, 4, 8, 56, 108, 5536, 28074040, 39648, 147312, 18566888967365603514688, 9966792788887776, 2775641472, 2505471397838180985096739296, 1445523368993397560000765219760086502994234237205516083525719052320, 44092571484448511101335177770183225655413760
Offset: 0
a(6) = 5536, because 5536 is a tetranacci number with 6 prime factors (counted with multiplicity) {2, 2, 2, 2, 2, 173} 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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