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枫谷剑仙's avatar
枫谷剑仙
Copper Contributor
Nov 14, 2025
Solved

Potential Bug: SEQUENCE Function Misbehaves with Dynamic start Parameter from BYROW/LAMBDA

Dear Microsoft Excel Team,   I’m encountering unexpected behavior when using SEQUENCE inside a BYROW/LAMBDA construction, specifically when the start parameter of SEQUENCE is derived from the lambd...
excel
office 365
  • Hecatonchire's avatar
    Hecatonchire
    Nov 14, 2025

    Hello.

    It's not a bug, but a trap!

    Simplified version of the formula.

    =BYROW({4;3}, LAMBDA(p,TEXTJOIN(" ",, SEQUENCE(5,,INDEX(p,1),4))))

     The SEQUENCE function expects a value for the Start argument, but it's an array of one value. Therefore, you need to extract the value from the array with INDEX.

    Edit : Not INDEX(p;1) but INDEX(p,1)

Patrick2788's avatar
Patrick2788
Silver Contributor
Nov 14, 2025

This is what Excel sees with 'k'

=BYROW(
    {4; 3},
    LAMBDA(p, LET(n, 4, k, p + 0, joined, TEXTJOIN(" ", , SEQUENCE(5, , k, n)), TYPE(k)))
)

output:
64
64

Workaround:
=BYROW({4; 3}, LAMBDA(p, LET(n, 4, k, p + 0, TEXTJOIN(" ", , SEQUENCE(5, , @k, n)))))

 

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