CoCalc -- Collaborative Calculation in the Cloud
Sharedsupport / 2015-03-31-183729-triangle.sagewsOpen in CoCalc

Examples for support purposes...

f(n) = n*(n+1)/2
f(5)
15
for i in [1..10]:
    print i, f(i)
1 1 2 3 3 6 4 10 5 15 6 21 7 28 8 36 9 45 10 55