

A098853


Consider the smallest denominator q such that the Sylvester expansion of n/q has n terms. Here q has the form q = k*n+1 and we set a(n) = k.


2



0, 1, 2, 4, 6, 18, 36, 12, 30, 162, 18, 330, 136, 858, 1092, 198, 1470, 882, 9520, 13260, 124800, 1216, 33966, 603060, 27742, 2141898, 677586
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OFFSET

1,3


LINKS



FORMULA



EXAMPLE

a(5)=6 because 5*6+1 = 31 and 5/31 = 1/7 + 1/55 + 1/3979 + 1/23744683 + 1/1127619917796295.


PROG

(PARI) a(n)=if(n==1, q=1, q=n+1; while(1, c=1; P=n; Q=q; while(Q%P>0, c++; D=Q\P+1; P=P*DQ; Q*=D); if(c==n, break); q+=n)); return((q1)/n)


CROSSREFS



KEYWORD

nonn,more


AUTHOR



EXTENSIONS



STATUS

approved



