1777555
domain: N
Appears in sequences
- Numbers that are n-gons for three or more n's, where n=3,4,5,...,16.at n=18A062712
- Number of inequivalent ways (mod D_4) three checkers can be placed on an n X n board.at n=20A082966
- Triangular numbers composed of digits {1,5,7}.at n=8A119134
- Sophie Germain triangular numbers tr: 2*tr+1 is also a triangular number.at n=9A124174
- Integers that are simultaneously triangular (A000217) and decagonal (A001107).at n=5A133216
- Decagonal hexagonal numbers.at n=2A203134
- Sequences A124174 and A006454 interlaced.at n=18A217278
- Triangular numbers (A000217) in A353729.at n=20A370520