This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A087948 #9 Oct 11 2017 05:07:53 %S A087948 1,4,5,9,16,17,18,25,36,37,39,49,64,65,66,68,81,100,101,105,121,126, %T A087948 144,145,146,147,150,169,196,197,203,225,256,257,258,260,264,289,324, %U A087948 325,327,333,361,400,401,402,405,410,441,484,485,495,529,576,577,578,579 %N A087948 Sum of successive remainders in computing euclidean algorithm for (1, -1/sqrt(-n)) has real and imaginary parts equal. %C A087948 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. %e A087948 kappa(-1/sqrt(-105)) = -(1/210 + (1/210)i)*sqrt(105). %o A087948 (MuPAD) kappa_neg_1_over_comp_sqrt := proc(n) local a,b,i,p; begin if (a := -sqrt(-n)+ceil(sqrt(-n))) = 0 then return(0) end_if: i := a := simplify(1/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(-(b/(p-1) + 1/a)/sqrt(-n),sqrt)); end_proc: %Y A087948 Cf. A086378, A087947. %K A087948 nonn %O A087948 1,2 %A A087948 _Thomas Baruchel_, Sep 07 2003