426426
domain: N
Appears in sequences
- Triangular numbers containing 2n digits obtained by duplicating the first n digits; i.e., triangular numbers in A020338.at n=6A068899
- Triangular numbers with only even digits.at n=22A117978
- Triangular numbers composed of digits {2,4,6}.at n=3A119160
- Triangle, read by rows, T(n, k) = A059481(n,k)*(A059481(n,k) - 1)/2.at n=26A171379
- The hyper-Wiener index of the linear phenylene with n hexagons.at n=12A224455
- Triangular arithmetic on half-squares: b(n)*(b(n) - 1)/2 where b(n) = floor(n^2/2).at n=43A227970
- Triangular numbers that are the product of a triangular number and an oblong number.at n=40A253652
- Triangular numbers that are palindromes in base 5.at n=13A350991
- Triangular numbers which are products of six distinct primes.at n=8A362758