OFFSET
1,7
LINKS
FORMULA
MAPLE
N:= 100: # for a(1)..a(N)
V:= Vector(N):
SF:= select(numtheory:-issqrfree, [$1..N]): nSF:= nops(SF):
P:= select(isprime, [2, seq(i, i=3..N/2)]):
SP:= sort(select(`<=`, [seq(seq(P[i]*P[j], i=1..j), j=1..nops(P))], N)): nSP:=
nops(SP):
j0:= 1:
for i from 1 to nSF while j0 <= nSP do
x:= SF[i];
while SP[j0] < x do
j0:= j0+1;
if j0 > nSP then break fi;
if SP[j0] + x > N then j0:= nSP+1; break fi;
od;
R:= select(`<=`, x +~ SP[j0 .. nSP], N);
V[R]:= V[R] +~ 1;
od:
convert(V, list); # Robert Israel, Apr 07 2020
MATHEMATICA
Table[Sum[MoebiusMu[i]^2 KroneckerDelta[PrimeOmega[n - i], 2], {i, Floor[n/2]}], {n, 100}]
CROSSREFS
KEYWORD
AUTHOR
Wesley Ivan Hurt, Apr 18 2018
STATUS
approved