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 A167182 a(n) = Product_{i=1..n-1} a(i) with a(1) = 2, a(2) = 4. 3
 2, 4, 8, 64, 4096, 16777216, 281474976710656, 79228162514264337593543950336, 6277101735386680763835789423207666416102355444464034512896 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS b(0) = 3; b(n+1) is the smallest number not in the sequence such that b(n+1) - Product_{i=0..n} b(i) divides b(n+1) + Product_{i=0..n} b(i). Then, b(n+1) = a(n) for n > 0. - Derek Orr, Jan 04 2015 Term a(13) has 925 decimal digits; a(14) has 1850 decimal digits. - Michael De Vlieger, Jan 07 2015 LINKS Michael De Vlieger, Table of n, a(n) for n = 1..13 FORMULA a(n) = (a(n-1))^2 for n > 3. a(n) = 2^A098011(n+1). - R. J. Mathar, Apr 22 2010 MATHEMATICA a167182[n_] := Block[{t = {2, 4}, f}, AppendTo[t, Times @@ t]; f[x_] := t[[x - 1]]^2; Do[AppendTo[t, f[i]], {i, 4, n}]; t]; a167182[9] (* Michael De Vlieger, Jan 07 2015 *) Join[{2, 4}, NestList[#^2&, 8, 10]] (* Harvey P. Dale, Nov 30 2019 *) CROSSREFS Cf. A165426. Sequence in context: A067507 A320898 A068994 * A058345 A093843 A270372 Adjacent sequences:  A167179 A167180 A167181 * A167183 A167184 A167185 KEYWORD nonn AUTHOR Giovanni Teofilatto, Oct 29 2009 EXTENSIONS Definition corrected by R. J. Mathar, Apr 22 2010 More terms from Vincenzo Librandi, Apr 25 2010 STATUS approved

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Last modified August 10 02:28 EDT 2020. Contains 336367 sequences. (Running on oeis4.)