What is row 1 in Pascals triangle?

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Answer 1 · 2015-07-15T22:32:13

Row 1 in Pascal's triangle consists of the single term #1#

The #n#th row of Pascal's triangle is:

#((n-1),(0))# #((n-1),(1))# ... #((n-1),(n-1))#

or if you prefer:

#((n-1)!)/(0!(n-1)!)# #((n-1)!)/(1!(n-2)!)# ... #((n-1)!)/((n-1)!0!)#

The 1st row just consists of

#((0),(0))#

or if you prefer:

#(0!)/(0!0!)#

Now #0! = 1#, hence #((0), (0)) = 1#

Answer 2 · 2015-07-16T14:44:36

I use the same counting as George C. The first row is row 1 and it is 1. However . . .

I have seen treatments that call the first row, "Row 0"

In that terminology, Row 1 is: #1# #1#

(and Row 2 is: #1# #2# #1#)

I assume that the reason for this is that it allows us to say that "Row #n# gives the coefficients of #(a+b)^n#".