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A240671
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Floor(4^n/(2+2*cos(2*Pi/7))^n).
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11
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1, 1, 1, 1, 2, 2, 3, 4, 5, 6, 8, 9, 12, 15, 18, 22, 28, 34, 42, 52, 64, 79, 98, 121, 149, 183, 226, 279, 343, 423, 521, 642, 791, 975, 1201, 1480, 1823, 2246, 2767, 3409, 4199, 5173, 6373, 7851, 9672, 11915, 14679, 18083
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OFFSET
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0,5
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COMMENTS
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a(n) is the perimeter (rounded down) of a heptaflake after n iterations, let a(0) = 1. The total number of sides is 7*A000302(n). The total number of holes is A023000(n).
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LINKS
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FORMULA
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MAPLE
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MATHEMATICA
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Table[Floor[4^n/(2 + 2*Cos[2*Pi/7])^n], {n, 0, 50}] (* Wesley Ivan Hurt, Apr 10 2014 *)
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PROG
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(PARI) {a(n)=floor(4^n/(2+2*cos(2*Pi/7))^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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