OFFSET
1,2
LINKS
Andrew Howroyd, Table of n, a(n) for n = 1..1000
FORMULA
Euler transform of A167934.
EXAMPLE
The 2^6 - a(7) = 5 compositions of 7 whose Lyndon prime factors are not all weakly increasing: (11212), (1132), (1213), (1321), (142).
MATHEMATICA
nn=50;
ser=Product[1/(1-x^n)^(PartitionsP[n]-DivisorSigma[0, n]+1), {n, nn}];
Table[SeriesCoefficient[ser, {x, 0, n}], {n, nn}]
PROG
(PARI) EulerT(v)={Vec(exp(x*Ser(dirmul(v, vector(#v, n, 1/n))))-1, -#v)}
seq(n)={EulerT(vector(n, n, numbpart(n) - numdiv(n) + 1))} \\ Andrew Howroyd, Dec 01 2018
CROSSREFS
KEYWORD
nonn
AUTHOR
Gus Wiseman, Feb 01 2018
STATUS
approved