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A240733
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Floor(6^n/(2+2*cos(Pi/9))^n).
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10
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1, 1, 2, 3, 5, 8, 13, 21, 32, 50, 78, 121, 187, 289, 448, 693, 1072, 1658, 2564, 3966, 6134, 9487, 14673, 22695, 35101, 54288, 83964, 129862, 200850, 310643, 480452, 743085, 1149282, 1777523, 2749182, 4251987, 6576279, 10171116, 15731022, 24330178, 37629950
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OFFSET
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0,3
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COMMENTS
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a(n) is the perimeter (rounded down) of a nonaflake after n iterations, let a(0) = 1. The total number of sides is 9*A000400(n). The total number of holes is A002452(n). 2*cos(Pi/9) = 1.87938524... = diagonal b of nonagon (see comments in A123609).
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LINKS
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MAPLE
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MATHEMATICA
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Table[Floor[6^n/(2 + 2*Cos[Pi/9])^n], {n, 0, 50}] (* Wesley Ivan Hurt, Apr 12 2014 *)
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PROG
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(PARI) {a(n)=floor(6^n/(2+2*cos(Pi/9))^n)}
for (n=0, 100, print1(a(n), ", "))
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CROSSREFS
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KEYWORD
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nonn,easy
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AUTHOR
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STATUS
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approved
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