A359880 a(n) is the smallest Fibonacci n-step number with exactly n prime factors (counted with multiplicity).
21, 44, 56, 120, 1936, 2000, 2035872, 32512, 265816832, 523008, 8565824256, 67047424, 134156288, 1073463296, 35176050802688, 8589344768, 562914520154112, 18013762856812544, 144112508021833728, 2305819919496904704, 1099509006336, 137438822400
Offset: 2
Keywords
Examples
a(3) = 44, because 44 is a tribonacci number with 3 prime factors (counted with multiplicity) {2, 2, 11} and this is the smallest such number.
Links
- Eric Weisstein's World of Mathematics, Fibonacci n-Step Number
- Eric Weisstein's World of Mathematics, Prime Factor