A heptagonal number is a figurate number that represents a heptagon. The n-th heptagonal number is given by the formula
- .
The first few heptagonal numbers are:
- 1, 7, 18, 34, 55, 81, 112, 148, 189, 235, 286, 342, 403, 469, 540, 616, 697, 783, 874, 970, 1071, 1177, 1288, 1404, 1525, 1651, 1782, … (sequence A000566 in OEIS)
Read more about Heptagonal Number: Parity, Generalized Heptagonal Numbers, Sum of Reciprocals
Famous quotes containing the word number:
“It is not the number of years we have behind us, but the number we have before us, that makes us careful and responsible and determined to find out the truth about everything.”
—George Bernard Shaw (1856–1950)