OFFSET
2,10
MAPLE
for n from 2 to 50 do s:=[0, 0]: t:=[seq(2*i-1, i=2..floor((n+1)/2))]:for n1 from 2 to n do i:= n1 mod 2 +1: for n2 in t do if(n1<>n2 and igcd(n1, n2)=1) then for n3 in t do if(n1<>n3 and n2<>n3 and igcd(n1, n3)=1 and igcd(n2, n3)=1) then for n4 in t do if(n1<>n4 and n2<>n4 and n3<>n4 and igcd(n1, n4)=1 and igcd(n2, n4)=1 and igcd(n3, n4)=1) then for n5 in t do if(n1<>n5 and n2<>n5 and n3<>n5 and n4<>n5 and igcd(n1, n5)=1 and igcd(n2, n5)=1 and igcd(n3, n5)=1 and igcd(n4, n5)=1) then s[i]:=s[i]+1 fi od fi od fi od fi od od: printf("%d, ", s[1]/4!+s[2]/5!) od: # C. Ronaldo
CROSSREFS
KEYWORD
nonn
AUTHOR
STATUS
approved