Where t(n) is the n-th 9-step Fibonacci number as defined by:
a(1...9)=1, a(n)=a(n-1)+a(n-2)+a(n-3)+a(n-4)+a(n-5)+a(n-6)+a(n-7)+a(n-8)+a(n-8)

t(74473) = 4221530356...3537061633
t(107070) = 2214452338...2504438793
t(170300) = 2527830426...4813375481
t(178994) = 6848199770...5021827201

Verified Fermat and Lucas PRP by pfgw.

To be completed...