A080095 Let sum(k>=0, k^n/(2*k+1)!) = (x(n)*e + y(n)/e)/z(n), where x(n) and z(n) are >0, then a(n)=z(n).

2, 8, 16, 16, 64, 128, 128, 512, 1024, 1024, 4096, 8192, 8192, 32768, 65536, 65536, 262144, 524288, 524288, 2097152, 4194304, 4194304, 16777216, 33554432, 33554432, 134217728, 268435456, 268435456, 1073741824, 2147483648

Offset: 1

Author

Benoit Cloitre and Paul D. Hanna, Jan 28 2003

Keywords

• nonn
• easy

Links

• Index to divisibility sequences

Crossrefs

Cf. A080093, A080094.

Programs

PARI

apply(n->2^n,Vec((1+2*x+x^2-x^3)/(1-x-x^3+x^4)+O(x^30))) \\ Charles R Greathouse IV, Apr 09 2012

Formula

a(n) = 2^b(n) and {b(n)}={1, 3, 4, 4, 6, 7, 7, 9, 10, 10, 12, 13, 13, 15, ..} where b(3n-2)=3n-2, b(3n-1)=3n, b(3n)=b(3n+1)=3n+1, for n>0.