because the species have the same m/z value (mass to charge ratio)
14n^2 - 33np -5p^2 =14n^2 -35np+ 2np -5p^2 .. (mid term breaking) = 7n(2n-5p) + p(2n-5p) =(2n-5p)(7n+p) here you go you are done =)
Given any number it is easy to find a rule based on a cubic polynomial (of order 3) such that the first three numbers are as listed in the question and the next is the given number. There are also non-polynomial solutions.The simplest quadratic isUn = 14n2 - 24n + 35 for n = 1, 2, 3, ... and accordingly, the next number in the sequence is 163.