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

Author

Ferenc Adorjan (fadorjan(AT)freemail.hu), Apr 11 2005

Keywords

• easy
• nonn

Comments

The n-nacci sequences are considered as defined in A000213, A000288, A000322, A000383 for n=3,4,5,6, respectively.

Examples

			a(3)=3 because tribonacci(3)=3 while fibonacci(3)=2;
a(6)=9 because hexanacci(9)=41 while fibonacci(9)=34.
		

Crossrefs

Cf. A105528, A000045, A000213, A000288, A000322, A000383.

Programs

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) }