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A193625 Decimal expansion of bicuspid curve area. 1
3, 7, 4, 6, 6, 0, 6, 9, 7, 8, 0, 3, 1, 2, 5, 1, 5, 4, 9, 4, 4, 0, 3, 6, 6, 7, 4, 1, 1, 9, 3, 8, 7, 5, 9, 5, 8, 7, 1, 6, 1, 2, 3, 1, 5, 7, 9, 0, 5, 2, 0, 3, 2, 6, 2, 3, 1, 3, 9, 0, 8, 2, 7, 5, 2, 7, 7, 7, 8, 6, 8, 8, 4, 9, 9, 6, 2, 5, 9, 0, 2, 1, 8, 4, 0, 4, 2, 2, 3, 7, 7, 6, 9, 6, 2, 5, 3, 0, 3, 8, 5, 6, 3, 7, 5 (list; constant; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..105.

Eric Weisstein's World of Mathematics, BicuspidCurve.

EXAMPLE

3.746606978...

MATHEMATICA

f[x_, y_] = (x^2 - 1)*(x - 1)^2 + (y^2 - 1)^2; sy = Solve[f[x, y] == 0, y]; sx = Solve[f[x, y] == 0, x]; s = Solve[f[x, -x + 1/2] == 0, x] ; f1[x_] = y /. sy[[4, 1]]; f2[x_] = y /. sy[[2, 1]]; g1[y_] = x /. sx[[3, 1]]; g2[y_] = x /. sx[[4, 1]]; x2 = x /. s[[3]]; y2 = f1[x2]; x6 = x /. s[[4]]; y6 = f2[x6]; ni[a_, b_] := NIntegrate[a, b, WorkingPrecision -> 120]; a1 = ni[f1[x] - 1, {x, x2, 1} ]; a2 = ni[x2 - g1[y], {y, 1, y2}]; a3 = ni[-g1[y], {y, 0, 1}]; a4 = ni[g2[y], {y, 0, y6}]; a5 = ni[1 - f2[x], {x, x6, 1}]; a6 = x6*(1 - y6); a = 2*(a1 + a2 + a3 + a4 + a5 + a6); Take[RealDigits[a][[1]], 105]

CROSSREFS

Cf. A193626 (length).

Sequence in context: A094689 A019831 A199733 * A198886 A305202 A192265

Adjacent sequences:  A193622 A193623 A193624 * A193626 A193627 A193628

KEYWORD

nonn,cons

AUTHOR

Jean-Fran├žois Alcover, Aug 01 2011

STATUS

approved

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Last modified April 5 19:11 EDT 2020. Contains 333257 sequences. (Running on oeis4.)