FORMULA TO SUM ALL ODD NUMBERS BETWEEN 1 TO 100

Formulas:

=SUM(2*ROW(OFFSET($A$1,,,100/2))-1) 

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=SUM(ROW(1:100)*MOD(ROW(1:100),2))

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=SUM(ROW(1:100)*ISODD(ROW(1:100)))

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All these formulas can be used for the same purpose