%0 Journal Article %T Shape of Numbers and Calculation Formula of Stirling Numbers %A Ji Peng %J Open Access Library Journal %V 7 %N 3 %P 1-11 %@ 2333-9721 %D 2020 %I Open Access Library %R 10.4236/oalib.1106081 %X 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. %K Combinatorics %K Shape of Numbers %K Stirling Numbers %K Congruence Formula %U http://www.oalib.com/paper/5426513