some puzzle seqs not in OEIS!

[N. J. A. Sloane]

Dear SeqFans,  There is an IQ test on the web, at URL
http://www.cpsimoes.net/tdm/tdm_uk.html
(in both Portugeuse and English, which rules out some of the 
more stupid letter substitution puzzles)

Here are the questions, with possible sequence numbers where I could identify them.
Some, e.g. #4, would be really hard without the OEIS (if A005542 is
really the answer)

Can anyone fill in any of the gaps?

Of course we don't have enough terms for this to
be really interesting.  I guess #1 is "double the previous term and 
add 2 or 1 or 0 or -1 ..." which would give 68 as the next term.
Similarly for #2.


Replace the question marks with the numbers that best complete the sequence 
1  1,4,9,18,35, ?  [double the previous term and add 2 or 1 or 0 or -1 ...]
2  23,45,89,177, ?  [double and subtract 1?]
3  -6,-8,0,32,120, ? 
4  1,2,3,4,8,10,14,20,22, ?    %N A005542 10*3^n - 1 is prime. (Maybe!)
5  1,6,21,52,105, ?    %N A069778 q-factorial numbers 3!_q. (Maybe!)
6  1,3,12,76, ?   %N A060946 Trace of Vandermonde matrix of numbers 1,2,..n, i.e. the matrix A with A[i,j] = i^j  (Maybe!)
7  1,6,18,44,90,174,294,472, ? 
8  2,3,6,10,11,14,18,19,22, ?  %N A047402 Congruent to {2, 3, 6} mod 8.
9  2,3,5,7,13,15,21,23,27, ?  %N A004682 Primes written in base 8.
10  1,2,5,9,16,26, ? Maybe %N A056870 Difference between partial sums of partition numbers (A026905) and partial sums of numbers of partitions into distinct parts (A026906).
11  2,4,3,6,10,7,14,16,15,18,22,19, ? 
12  2,4,5,6,9,10,15,16,20, ? 
13  4,1,4,2,1,3,5, ?  %N A002193 Decimal expansion of square root of 2.
14  6,21,105,301,1221, ?  [p(p^2-p+1) as p runs through the primes]
15  2,2,1,3,2,3,4,2,6,5,2, ? 
16  1,8,24,64,126,202, ? 
17  36, 864, 21060, 544320, ? 
18  2,7,17,31,59,83,125, ? 
19  2,6,20,70,252,924,3432, ?  %N A000984 Central binomial coefficients: C(2n,n) = (2n)!/(n!)^2.
20  1, 2, 9, 48, 300, 2160, ?   %N A074143 a(1) = 1; a(n) = n * sum {a(k) | k < n}.

NJAS