This article investigated the idea of Shape of numbers and introduced new operators. The idea divides all products of k distinct integers in [1, n ？ 1] into 2K？1 catalogs and derives the calculation formula of every catalog. As a simple deduction, a direct formula of the Stirling numbers of the first kind S1(n, n ？ k) and a simple recursive formula of Stirling numbers of the second kind S2(n, n ？ k) are obtained. By analyzing the Shape of numbers, new congruence formulas are obtained.
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