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A087947
Sum of successive remainders in computing Euclidean algorithm for (1, 1/sqrt(-n)) has real and imaginary parts equal.
1
1, 4, 5, 6, 8, 9, 16, 17, 18, 20, 24, 25, 36, 37, 38, 39, 40, 42, 48, 49, 64, 65, 66, 68, 72, 78, 80, 81, 100, 101, 102, 104, 105, 110, 117, 120, 121, 144, 145, 146, 147, 148, 150, 152, 155, 156, 164, 168, 169, 196, 197, 198, 200, 203, 210, 220, 222, 224, 225, 256
OFFSET
1,2
COMMENTS
Since the computation of the algorithm needs an extension of the integer part over a subset of C, the rule: floor(I*x) = i*floor(x) is used (which is what MuPAD does). The following program computes the exact value of the sum.
For all a(n) in the sequence, the relation: (2k)^2 <= a(n) <= (2k+1)^2 is true.
EXAMPLE
kappa(1/sqrt(-203)) = (1/2 + (1/2)i) - (1/29 + (1/29)i)*sqrt(203).
PROG
(MuPAD) kappa_1_over_comp_sqrt := proc(n) local a, b, i, p; begin if (a := sqrt(-n)-isqrt(-n)) = 0 then return(0) end_if: a := simplify(1/a, sqrt); i := a := simplify(1/(a - floor(a)), sqrt); p := 1; b := 0; repeat p := p*a; b := b*a+a-floor(a); until (a := simplify(1/(a-floor(a)), sqrt)) = i end_repeat: return(simplify((1-isqrt(n)/sqrt(n))*(1+b/(p-1)+1/a-floor(1/a)), sqrt)); end_proc:
CROSSREFS
Sequence in context: A047432 A095279 A030751 * A053427 A272054 A037354
KEYWORD
nonn
AUTHOR
Thomas Baruchel, Sep 07 2003
STATUS
approved