OFFSET
1,22
COMMENTS
A relatively prime or monic partition of n is an integer partition of n that is either of length 1 (monic) or whose parts have no common divisor other than 1 (relatively prime).
MATHEMATICA
a[n_]:=a[n]=If[n===1, 1, 0]-Sum[Times@@a/@y, {y, Rest[Select[IntegerPartitions[n], Or[Length[#]===1, GCD@@#===1]&]]}];
Array[a, 20]
CROSSREFS
KEYWORD
sign
AUTHOR
Gus Wiseman, Apr 15 2018
STATUS
approved