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A088235
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Total number of digits (in base 10) in all preceding terms in the sequence.
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4
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0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 12, 14, 16, 18, 20, 22, 24, 26, 28, 30, 32, 34, 36, 38, 40, 42, 44, 46, 48, 50, 52, 54, 56, 58, 60, 62, 64, 66, 68, 70, 72, 74, 76, 78, 80, 82, 84, 86, 88, 90, 92, 94, 96, 98, 100, 103, 106, 109, 112, 115, 118, 121, 124, 127, 130, 133
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OFFSET
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0,3
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LINKS
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FORMULA
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a(n+1) = a(n) + floor(Log(10, a(n))) + 1, with a(0) = 0, a(1) = 1.
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MATHEMATICA
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a[n_]:= a[n]= If[n<2, n, a[n-1] +Floor[Log10[a[n-1]]] +1];
Table[a[n], {n, 0, 100}] (* G. C. Greubel, Dec 10 2015; Jul 24 2022 *)
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PROG
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(PARI) lista(nn) = {ns = 0; v = vector(nn); for (i=2, nn, ns += #Str(v[i-1]); v[i] = ns; ); v; } \\ Michel Marcus, Dec 05 2015
(SageMath)
@CachedFunction
def a(n): return n if (n<2) else a(n-1) + floor(log(a(n-1), 10)) + 1 # a = A088235
(Python)
from itertools import islice
def agen():
an = 0
while True: yield an; an += len(str(an))
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CROSSREFS
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KEYWORD
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base,easy,nonn
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AUTHOR
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David Corbett (dcorbett42(AT)yahoo.co.nz), Sep 25 2003
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EXTENSIONS
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STATUS
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approved
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