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 A109070 Number of digits in numbers appearing in A108225. 1
 1, 1, 1, 1, 2, 2, 4, 7, 13, 25, 50, 99, 196, 392, 783, 1566, 3131, 6261, 12521, 25042, 50084, 100166, 200332, 400663, 801325, 1602649, 3205298, 6410595, 12821190, 25642379, 51284758 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,5 COMMENTS Starting with a(14)=783, a(n) = 2*a(n-1) - (1 or 0). LINKS EXAMPLE A109070(10)=50 because A108225(10)=16217557574922386301420536972254869595782763547562 has 50 digits. MATHEMATICA nxt[{a_, b_}]:={b, ((a+b)(b-a+1))/2}; Join[{1}, IntegerLength/@ Transpose[ NestList[nxt, {0, 2}, 31]][[2]]] (* Harvey P. Dale, Feb 14 2012 *) CROSSREFS Cf. A108225. Sequence in context: A325908 A153970 A067953 * A169973 A300353 A049868 Adjacent sequences:  A109067 A109068 A109069 * A109071 A109072 A109073 KEYWORD base,nonn AUTHOR Zak Seidov, Jun 18 2005 STATUS approved

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Last modified December 15 11:43 EST 2019. Contains 329999 sequences. (Running on oeis4.)