1053426

Appears in sequences

• Expansion of e.g.f. exp(arctanh(x)/exp(x)).at n=11A013573
• Triangular numbers whose digits can be rearranged to form a substring of 123456789012345678901234....at n=28A068804
• Least triangular number whose digit permutations yield exactly n further triangular numbers.at n=9A095870
• Least triangular number whose digits include a permutation of {0,1,...,n}.at n=6A111482
• Smallest triangular number with exactly n anagrams that are triangular numbers.at n=7A166596
• Triangular numbers which have one or more occurrences of exactly seven different digits.at n=2A241790
• Non-coprime pseudoprimes to base 3 (A306451) that are not squarefree.at n=1A306450
• Non-coprime pseudoprimes or primes to base 3: numbers k that are multiples of 3 and are such that k divides 3^k - 3.at n=17A306451
• Pseudoprimes to base 3 that are not squarefree, including the non-coprime pseudoprimes.at n=19A306452