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A190289
Decimal expansion of (3+sqrt(21))/4.
2
1, 8, 9, 5, 6, 4, 3, 9, 2, 3, 7, 3, 8, 9, 6, 0, 0, 0, 1, 6, 4, 7, 0, 1, 1, 7, 9, 8, 4, 3, 2, 0, 0, 2, 1, 2, 2, 2, 4, 6, 1, 1, 4, 1, 4, 4, 1, 9, 1, 9, 9, 2, 9, 7, 5, 6, 5, 1, 8, 1, 0, 5, 3, 0, 9, 7, 6, 7, 1, 7, 1, 0, 6, 3, 8, 6, 9, 4, 2, 7, 2, 1, 6, 5, 1, 0, 9, 0, 3, 8, 9, 8, 7, 3, 3, 6, 1, 2, 5, 8, 1, 6, 9, 4, 0, 0, 2, 2, 6, 3, 4, 9, 3, 9, 6, 4, 3, 5, 2, 1
OFFSET
1,2
COMMENTS
The rectangle R whose shape (i.e., length/width) is (3+sqrt(21))/4, can be partitioned into rectangles of shapes 3/2 and 2 in a manner that matches the periodic continued fraction [3/2, 2, 3/2, 2, ...]. R can also be partitioned into squares so as to match the periodic continued fraction [1,1,8,1,1,2,1,1,8,1,1,2,,...]. For details, see A188635.
EXAMPLE
1.895643923738960001647011798432002122246...
MATHEMATICA
FromContinuedFraction[{3/2, 2, {3/2, 2}}]
ContinuedFraction[%, 100] (* [1, 1, 8, 1, 1, 2, ... *)
RealDigits[N[%%, 120]] (* A190289 *)
N[%%%, 40]
RealDigits[(3+Sqrt[21])/4, 10, 120][[1]] (* Harvey P. Dale, Dec 13 2019 *)
CROSSREFS
KEYWORD
nonn,cons
AUTHOR
Clark Kimberling, May 07 2011
STATUS
approved