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 A129099 a(n) = Sum_{k=2^(n-1)..2^n-1} A129095(k) for n>=1. 4
 1, 4, 20, 136, 1376, 22176, 591680, 26770688, 2096125184, 289083462144, 71239716616192, 31730665042094080, 25779103986580017152, 38488216155785101459456, 106257557996370396596748288, 545336631331873524033714683904 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS b(n)=A129095(n) obeys the recurrence: b(n) = b(n/2) (n even), b(n) = 2*b(n-1) + b(n-2) (n odd >1), with b(1) = 1. LINKS FORMULA a(n) = ( A129097(n+1) - A129097(n) )/2. MATHEMATICA Block[{e = 16, s}, s = Nest[Append[#1, If[EvenQ[#2], #1[[#2/2]], 2 #1[[-1]] + #1[[-2]] ] ] & @@ {#, Length@ # + 1} &, {1}, 2^e]; Array[Total@ s[[2^# ;; 2^(# + 1) - 1]] &, e, 0] ] (* Michael De Vlieger, Mar 10 2020 *) PROG (PARI) CROSSREFS Cf. A129095, A129096, A129097, A129098. Sequence in context: A330538 A141716 A129102 * A244756 A292932 A187116 Adjacent sequences:  A129096 A129097 A129098 * A129100 A129101 A129102 KEYWORD easy,nonn AUTHOR Paul D. Hanna, Apr 11 2007 EXTENSIONS a(16) from Michael De Vlieger, Mar 10 2020 STATUS approved

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Last modified January 24 17:24 EST 2021. Contains 340411 sequences. (Running on oeis4.)