anciently signified a letter sealed with the king's seal.

Programma is also an university term for a billet or advertisement, posted up or given into the hand, by way of invitation to an oration, &c., containing the argument, or so much as is necessary for understanding thereof.

Thus \[ \{ a, a+d, a+2d, a+3d, \ldots \} \] &c. increasing by the difference \( d \).

In numbers \[ \{ 2, 4, 6, 8, 10, \ldots \} \] &c. increasing by the difference 2.

Geometric Progression, or Continued Geometric Proportion, is when the terms do increase or decrease by equal ratios: thus,

\[ \{ a, ar, arr, arrr, \ldots \} \] &c. increasing

\[ \{ \frac{a}{r}, \frac{a}{rr}, \frac{a}{rrr}, \ldots \} \] &c. decreasing

\[ \{ 2, 4, 8, 16, 32, 64, \ldots \} \] increasing

\[ \{ 64, 32, 16, 8, 4, 2, \ldots \} \] decreasing

See the articles Fluxions, Geometry, and Series.