A359853 -id:A359853 - cp's OEIS frontend

A359852 a(n) is the smallest Fibonacci n-step number with exactly n distinct prime factors.

21, 504, 39648, 6930, 12669125245488, 471771076278370, 32818036405994618064, 71577732779401085355729600, 204945946670840805166309694624676331385919836360545974559162291811394735721440

Offset: 2

Ilya Gutkovskiy, Jan 15 2023

nonn

			a(3) = 504, because 504 is a tribonacci number with 3 distinct prime factors {2, 3, 7} and this is the smallest such number.

Eric Weisstein's World of Mathematics, Distinct Prime Factors
Eric Weisstein's World of Mathematics, Fibonacci n-Step Number

Cf. A001221, A060319, A359848, A359849, A359853.

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

a(10) from Jinyuan Wang, Jan 16 2023

A359881 a(n) is the index of the smallest Fibonacci n-step number with exactly n prime factors (counted with multiplicity).

Original entry on oeis.org

8, 9, 10, 12, 17, 18, 29, 24, 38, 30, 45, 39, 41, 45, 61, 50, 67, 73, 77, 82, 62, 60, 71, 70, 127, 161, 112, 111, 86, 154, 91, 127, 99, 100, 141, 109, 109, 115, 159, 122, 122, 125, 131, 133, 134, 329, 138, 147, 196, 407, 150, 256, 320, 165, 163, 223, 170, 173

Offset: 2

Ilya Gutkovskiy, Jan 16 2023

nonn

Eric Weisstein's World of Mathematics, Fibonacci n-Step Number
Eric Weisstein's World of Mathematics, Prime Factor

Cf. A001222, A072396, A359853, A359878, A359879, A359880.

a(24)-a(59) from Daniel Suteu, Jan 18 2023

cp's OEIS Frontend

A359852 a(n) is the smallest Fibonacci n-step number with exactly n distinct prime factors.

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