A068894 a(1) = 1; a(n) is the smallest n-th power which is congruent to 1 mod a(n-1).

1, 4, 125, 10556001, 131068195168072318688258971724480032

Offset

1,2

Links

Table of n, a(n) for n=1..5.

Example

a(3) = 125 = 5^3 = 31*a(2) + 1 where a(2) = 4=2^2 = 3*1 + 1.

Prog

(PARI) v=vector(15):v[2]=4:print1("1, 4, "):for(n=3, 15, for(k=2, 10^8, if(((k^n)%(v[n-1]))==1, print1(k^n", "):v[n]=k^n:break)))

Crossrefs

Sequence in context: A195797 A354549 A286017 * A116944 A124260 A253099

Adjacent sequences: A068891 A068892 A068893 * A068895 A068896 A068897

Keyword

nonn

Author

Amarnath Murthy, Mar 20 2002

Extensions

Corrected and extended by Ralf Stephan, Mar 21 2003

Status

approved