n1 (The default is 3.)

    Specifies the lowest-numbered header level to have the section
    title run-in to the paragraph that it heads. The text immediately
    follows the header title on the same line instead of beginning
    a new paragraph. All higher-numbered levels also have run-in
    formats. If n1=4, then .HEADER LEVEL 4, 5, and 6 titles are
    run into the main text. All lower levels will have the title
    separated from the text by blank lines (see parameter n7 for
    number of blank lines).

 n2 (The default is 1.)

    Specifies the highest-numbered header level to have its title
    printed entirely in uppercase. All lower-numbered levels will
    also have titles entirely in uppercase. If n2=4, then .HEADER
    LEVEL 1, 2, 3, and 4 will have titles in uppercase.

 n3 (The default is 6.)

    Specifies the highest-numbered header level to have only the
    first letter of each word capitalized in the title. All lower-
    numbered levels will also have titles in mixed format. If n3=6,
    all levels will have this case format. All uppercase takes
    precedence over initial capital letters, if there is a conflict.

 n4 (The default is 7.)

    Specifies the lowest-numbered header level not to have a
    section number to the left of its title. All higher-numbered
    levels will also not have section numbers to the left of their
    titles. Because there are only 6 header levels, the default of 7
    indicates that all headers numbered.

 n5 (The default is 7.)

    Specifies the lowest numbered non-run-in header level to have
    its title centered. All higher-numbered non-run-in levels will
    also have their titles centered. Because there are only 6 header
    levels, the default value of 7 indicates that no header titles
    are centered.

 n6 (The default is 3.)

    Specifies the number of blank lines you want before section
    heads.

 n7 (The default is 1.)

    Specifies the number of blank lines you want after non-run-in
    section heads before the text is printed.

 n8 (The default is 9.)

    Specifies the number of lines you want to have available on the
    current page for the test page issued by .HEADER LEVEL. Note that
    n8 takes into account any blank lines that .SPACING routinely
    inserts after each line of text (unlike .TEST PAGE). (See also
    .SKIP.)

 n9 (The default is 2.)

    Specifies the number of spaces you want between the section
    number and the section title. The maximum value is 75.