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A053480
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Sum of values when cototient function A051953 is iterated until fixed point is reached.
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1
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1, 3, 4, 7, 6, 13, 8, 15, 13, 23, 12, 27, 14, 29, 23, 31, 18, 45, 20, 47, 34, 49, 24, 55, 31, 55, 40, 59, 30, 79, 32, 63, 47, 79, 47, 91, 38, 85, 62, 95, 42, 121, 44, 99, 79, 101, 48, 111, 57, 129, 71, 111, 54, 145, 78, 119, 91, 137, 60, 159, 62, 125, 103, 127, 83, 167
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OFFSET
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1,2
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LINKS
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FORMULA
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a(n) = Sum[Nest[co, n, j], {j, 1, x[n]}]; co[n]=A051953[n], x[n] is the number of iterations
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EXAMPLE
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If n=130 and A051953 is iterated, we obtain {130,82,42,30,22,12,8,4,2,1,0}. The sum of these terms is 130 + 92 + 42 + 30 + 12 + 8 + 4 + 2 + 1 = 333, so a(130)=333.
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MATHEMATICA
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Array[Total@ Most@ NestWhileList[# - EulerPhi@ # &, #, # > 0 &] &, 66] (* Michael De Vlieger, Nov 20 2017 *)
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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