13, 26, 39, 52, 65…
= + d(n – 1)
() = (13) + (13)[(50) – 1]
= 13 + 13 · 49
= 13 + 637
= 650
= ( + )
() = [(13) + (650)]
= 25 · 663
= 16575
13, 26, 39, 52, 65…
= + d(n – 1)
() = (13) + (13)[(50) – 1]
= 13 + 13 · 49
= 13 + 637
= 650
= ( + )
() = [(13) + (650)]
= 25 · 663
= 16575