18, 46, 94, 63, 52. According to this rule, what's the next number? Why?

18, 46, 94, 63, 52. According to this rule, what's the next number? Why?

18.46.94.63.52 can be regarded as 81,64,49,36,25
And 81, 64, 49, 36 and 25 are the squares of 9, 8, 7, 6 and 5 respectively And so on, it's 4 squared 16, and the reverse is 61

5 / 8 * 5 / 12 + 7 / 12 * 15 + 5 / 8 (simple algorithm)

7 / 12 * 15 = 105 / 12, so we can get 5 / 8 * 5 / 12 + 105 / 12 + 5 / 8 = 5 / 8 * (5 / 12 + 105 / 12) = 5 / 8 * 110 / 12 = 275 / 48

Using simple algorithm to calculate 72 times 0.98 + 7.2 times 0.2

72 times 0.98 + 7.2 times 0.2
=72×0.98+72×0.02
=72×（0.98+0.02）
=72×1
=72