Question: How to Properly Display a Table of Numerical Results in Maple?

I'm working on solving a system of ODEs in Maple that models an epidemic scenario, tracking the number of susceptible, infected, and recovered individuals over time. Here's what I've done so far:
Download sir_model.mw

Created a table of results at daily intervals with the following code:

results := [seq([t = tval, s = round(evalf(sol(tval)[2][1])), i = round(evalf(sol(tval)[2][2])),r = round(evalf(sol(tval)[2][2]))], tval = 0 .. 50)];

printf("%-10s %-15s %-15s %-15s\n", "Day", "Infected", "Recovered");
printf("---------------------------------------------\n");
for entry in results do
    printf("%-10d %-15d %-15d %-15d\n", entry[t],entry[s], entry[i], entry[r]);
end do;

but I encountered an error (in fprintf) integer expected for integer format