足し算の順序の変更

足し算の順序の変更
結合法則: (a + b) + c = a + (b + c)

1: \sum_i \sum_j f(i, j) = \sum_j \sum_i f(i, j)

"Engineer's way of creating knowledge" the English version of my book is now available on [Engineer's way of creating knowledge]

(C)NISHIO Hirokazu / Converted from [Scrapbox] at 11/23/2025, 5:45:10 PM[Edit]