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A076698
a(1) = 2, a(n+1) = smallest squarefree number == 1 (mod a(n)).
1
2, 3, 7, 15, 31, 94, 95, 191, 383, 767, 1535, 3071, 6143, 12287, 36862, 36863, 73727, 147455, 294911, 589823, 1179647, 2359295, 4718591, 9437183, 18874367, 37748735, 75497471, 150994943, 301989887, 905969662, 905969663, 1811939327
OFFSET
1,1
MAPLE
with(numtheory):a[1] := 2:for n from 2 to 84 do q := a[n-1]+1:while(not issqrfree(q)) do q := q+a[n-1]:od:a[n] := q:od:seq(a[l], l=1..84);
MATHEMATICA
a[1] = 2; a[n_] := a[n] = Block[{k = 1}, While[ MoebiusMu[k*a[n - 1] + 1] == 0, k++ ]; k*a[n - 1] + 1]; Table[ a[n], {n, 1, 32}]
CROSSREFS
Sequence in context: A372889 A153010 A076993 * A323598 A078007 A368410
KEYWORD
nonn
AUTHOR
Amarnath Murthy, Oct 26 2002
EXTENSIONS
Edited and extended by Robert G. Wilson v, Oct 29 2002
STATUS
approved