OFFSET
1,3
FORMULA
The sequence can be generated from strings of 2^n terms starting (1, 1,... then the next string of 2^(n+1) terms is obtained by appending a "reverse and increment" substring to the previous substring.
EXAMPLE
Given terms in the Bell sequence, A000110; A165195 begins (1, 1, 2, 1,... then to obtain the first 2^3 terms, the first 2^2 terms = (1, 1, 2, 1,... then append to the latter the reversal of (1, 1, 2, 1) = (1, 2, 1, 1) but incremented with the next higher Bell number = (2, 5, 2, 1). The first 2^3 terms are thus (1, 1, 2, 1, 2, 5, 2, 1). Repeat with analogous operations to obtain 2^4 terms, and so on..
CROSSREFS
KEYWORD
nonn
AUTHOR
Gary W. Adamson, Sep 06 2009
STATUS
approved