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%I #6 Feb 14 2014 09:34:26
%S 1,6,24,24,100,24,112,96,216,300,110,24,364,336,600,384,612,216,342,
%T 600,336,330,1104,96,2500,1092,1944,336,406,600,930,1536,1320,612,
%U 2800,216,2812,342,2184,2400,1640,336,3784,1320,5400,1104,1504,384,5488,7500
%N Pisano period of n^2.
%H Charles R Greathouse IV, <a href="/A237836/b237836.txt">Table of n, a(n) for n = 1..10000</a>
%F a(n) = A001175(n^2).
%o (PARI) fibmod(n, m)=((Mod([1, 1; 1, 0], m))^n)[1, 2]
%o entry_p(p)=my(k=1, c=Mod(1, p), o); while(c, [o, c]=[c, c+o]; k++); k
%o entry(n)=if(n==1, return(1)); my(f=factor(n), v); v=vector(#f~, i, if(f[i, 1]>1e14, entry_p(f[i, 1]^f[i, 2]), entry_p(f[i, 1])*f[i, 1]^(f[i, 2] - 1))); if(f[1, 1]==2&&f[1, 2]>1, v[1]=3<<max(f[1, 2]-2, 1)); lcm(v)
%o per(n)=if(n==1, return(1)); my(k=entry(n)); forstep(i=k, n^2, k, if(fibmod(i-1, n)==1, return(i)))
%o a(n)=per(n^2)
%Y Cf. A001175, A001176, A237517, A237835.
%K nonn
%O 1,2
%A _Charles R Greathouse IV_, Feb 13 2014
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