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%I #11 Oct 13 2024 07:08:15
%S 1,1,5,32,348,4520,76840,1459949,33578823,973785863,30187361738,
%T 1116932384273,45794227755181,1969151793472765,92550134293219955,
%U 4905157117540657588,289404269934898797687,17653660466028826658882,1182795251223931386145053,83978462836899128416298742
%N a(n) = number of digits in the decimal expansion of A046967(n).
%C All the terms in A046967 are of the form 2^k.
%F From _Amiram Eldar_, Oct 13 2024: (Start)
%F a(n) = A055642(A046967(n)).
%F a(n) = floor(log_10(2) * A070826(n)). (End)
%t a = {}; c = 2; Do[d = Length[IntegerDigits[c, 10]]; c = c^Prime[n]; AppendTo[a, d], {n, 2, 9}]; a
%t IntegerLength/@RecurrenceTable[{a[1]==2,a[n]==a[n-1]^Prime[n]}, a[n], {n,9}] (* _Harvey P. Dale_, Jul 18 2011 *)
%t 1 + Floor[Log10[2] * FoldList[Times, 1, Prime[Range[2, 20]]]] (* _Amiram Eldar_, Oct 12 2024 *)
%Y Cf. A007524, A046967, A055642, A070826, A135249.
%K base,nonn
%O 1,3
%A _Artur Jasinski_, Nov 24 2007
%E a(9) from Harvey P. Dale, Jul 18 2011
%E More terms from _Amiram Eldar_, Oct 12 2024