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A129953
First differences of A129952.
6
0, 1, 4, 10, 24, 56, 128, 288, 640, 1408, 3072, 6656, 14336, 30720, 65536, 139264, 294912, 622592, 1310720, 2752512, 5767168, 12058624, 25165824, 52428800, 109051904, 226492416, 469762048, 973078528, 2013265920, 4160749568
OFFSET
0,3
FORMULA
a(n) = A129952(n+1) - A129952(n).
a(n) = A087447(n) for n > 0.
a(0) = 0, a(1) = 1; for n > 1, a(n) = (n+2)*2^(n-2).
G.f.: x*(1-2*x^2)/(1-2*x)^2.
PROG
(Magma) m:=16; S:=&cat[ [ 1, 2*i ]: i in [0..m] ]; T:=[ &+[ Binomial(j-1, k-1)*S[k]: k in [1..j] ]: j in [1..2*m] ]; [ T[n+1]-T[n]: n in[1..2*m-1] ]; // Klaus Brockhaus, Jun 17 2007
(PARI) {m=29; print1(0, ", ", 1, ", "); for(n=2, m, print1((n+2)*2^(n-2), ", "))} \\ Klaus Brockhaus, Jun 17 2007
(Python)
def A129953(n): return n+2<<n-2 if n>1 else n # Chai Wah Wu, Oct 03 2024
CROSSREFS
Sequence in context: A090855 A052252 A087447 * A079859 A298802 A118871
KEYWORD
nonn,easy
AUTHOR
Paul Curtz, Jun 10 2007
EXTENSIONS
Edited and extended by Klaus Brockhaus, Jun 17 2007
STATUS
approved