login
A164703
a(n) = 8*a(n-2) for n > 2; a(1) = 1, a(2) = 16.
2
1, 16, 8, 128, 64, 1024, 512, 8192, 4096, 65536, 32768, 524288, 262144, 4194304, 2097152, 33554432, 16777216, 268435456, 134217728, 2147483648, 1073741824, 17179869184, 8589934592, 137438953472, 68719476736, 1099511627776
OFFSET
1,2
COMMENTS
Interleaving of A001018 and 16*A001018.
Binomial transform is A164602.
FORMULA
a(n) = (3+(-1)^n)*2^(1/4*(6*n-7+3*(-1)^n)).
G.f.: x*(1+16*x)/(1-8*x^2).
MATHEMATICA
Riffle[#, 16*#] & [8^Range[0, 14]] (* or *)
LinearRecurrence[{0, 8}, {1, 16}, 30] (* Paolo Xausa, Apr 22 2024 *)
PROG
(Magma) [ n le 2 select 15*n-14 else 8*Self(n-2): n in [1..26] ];
CROSSREFS
Cf. A001018 (powers of 8), A164602.
Sequence in context: A040243 A299584 A213558 * A153724 A183396 A070535
KEYWORD
nonn,easy
AUTHOR
Klaus Brockhaus, Aug 23 2009
STATUS
approved