SERIESSUM in Collabora Office: Evaluate Polynomials with Explicit Powers and Coefficients

• Introduced: original Collabora release and launch date are not established by the sources reviewed.
• Availability: documented in Collabora Office 26.04 help, scoped to the desktop-help release.
• Platform scope: support in every online or mobile deployment is not inferred from desktop documentation.
• Checked: October 14, 2026. Function-specific documentation and independently derived controls; no native Collabora test was performed.

=SERIESSUM(x;n;m;coefficients)

x is the input value, n is the first exponent, and m is the change in exponent between successive coefficients. The coefficient range contributes one term per coefficient:

c1*x^n + c2*x^(n+m) + c3*x^(n+2*m) + ...

The official Collabora page documents this formula. It computes the finite terms supplied; it does not automatically choose how many terms are needed for an accurate infinite-series approximation. The examples use English names, semicolon separators and explicit numeric coefficient cells.

Enter coefficients 2, −3, 4 in B2:B4 in that order. Put 2 in A2 and use:

=SERIESSUM(A2;0;1;B2:B4)

Expected result: 12. The exponents are 0, 1 and 2, so the terms are 2, −6 and 16.

For a copied-input table, put −1, 1, 2, 3 in D2:D5. In E2 enter and fill down:

=SERIESSUM(D2;0;1;$B$2:$B$4)

Expected outputs are 9, 3, 12, 29. The absolute coefficient range stays fixed while the input cell moves. Reversing the coefficient order would define a different polynomial.

Put coefficients 3, −2, 1 in G2:G4. Then:

=SERIESSUM(2;1;2;G2:G4)

Expected result: 22, from 3×2¹−2×2³+1×2⁵ = 6−16+32. Starting at exponent one and stepping by two produces 1, 3 and 5, not 1, 2 and 3.

Keep the initial exponent and increment visible when the series is not an ordinary polynomial with every degree present. A wrong exponent step can leave the formula syntactically valid while changing every term after the first.

Suppose the intended polynomial is 5+2*x^2. Put 5, 0, 2 in J2:J4 and calculate:

=SERIESSUM(3;0;1;J2:J4)

Expected result: 23. The explicit zero occupies the coefficient of x¹. If the zero is removed and the coefficient list becomes just 5, 2, the same start and step instead describe 5+2*x, giving 11 at x=3.

Use numeric zero for an intentionally absent degree rather than relying on undocumented blank-cell handling. A coefficient’s position determines its exponent.

In M2:M4 enter numeric 1, =-1/2 and =1/24. These are coefficients for 1−x²/2+x⁴/24. At x=0.5:

=SERIESSUM(0.5;0;2;M2:M4)

Expected approximation: 0.877604167. The mathematical COS value at 0.5 radians is approximately 0.877582562, so the approximation is higher by about 0.000021605.

At x=1 the same finite series gives approximately 0.541666667, while COS(1) is approximately 0.540302306, a difference of about 0.001364361. A short approximation can become less accurate farther from its expansion point. SERIESSUM performs the supplied sum; the analyst must choose and validate the approximation.

The term x^exponent must be meaningful for the chosen inputs. Negative or fractional exponents introduce domain considerations, and zero raised to some powers requires special attention. The examples avoid zero-base boundary conventions.

The direct source does not provide a complete coefficient-type, array-shape, error or precision matrix. Large powers and cancellation between terms can also affect numerical results. Inspect individual terms and compare against an independently justified result when adapting the series.

• Collabora Office 26.04: SERIESSUM.
• Editorial testing standards.

The direct product reference establishes the function definition and syntax. Worked examples were independently calculated; no native Collabora execution or broader client certification is claimed.