A105527 Index when n-nacci (tribonacci etc.) passes Fibonacci numbers.
3, 4, 6, 9, 11, 14, 16, 19, 22, 25, 27, 30, 33, 36, 39, 42, 45, 48, 51, 54, 57, 60, 63, 67, 70, 73, 76, 79, 82, 85, 88, 91, 95, 98, 101, 104, 107, 110, 113, 117, 120, 123, 126, 129, 132, 136, 139, 142, 145, 148, 151, 155, 158, 161, 164, 167, 171, 174, 177, 180, 183, 186
Offset: 3
Examples
a(3)=3 because tribonacci(3)=3 while fibonacci(3)=2; a(6)=9 because hexanacci(9)=41 while fibonacci(9)=34.
Programs
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PARI
{n_bonacci(n,v)= local(x,l);l=matsize(v)[2]; x=0;for(i=l-n+1,l,x+=v[i]);return(x)} {nbg(k)= local(q=[],l,v,m); for(n=3,k,v=[];for(i=1,n,v=concat(v,1));m=n; while((x=n_bonacci(n,v))<=fibonacci(m),v=concat(v,x);m+=1);q=concat(q,m)); return(q) }
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