def isPentagonal(n):
soln = quad_formula(3, -1, -2*n)
if soln[0] > 0 and soln[0] == int(soln[0]) or soln[1] > 0 and soln[1] == int(soln[1]):
return True
else:
return False
def isHexagonal(n):
soln = quad_formula(2, -1, -n)
if soln[0] > 0 and soln[0] == int(soln[0]) or soln[1] > 0 and soln[1] == int(soln[1]):
return True
else:
return False
def isTriangular(n):
soln = quad_formula(1, 1, -2*n)
if soln[0] > 0 and soln[0] == int(soln[0]) or soln[1] > 0 and soln[1] == int(soln[1]):
return True
else:
return False
