1631432881

Appears in sequences

• Square triangular numbers: numbers that are both triangular and square.at n=7A001110
• Squares (A000290) which are also hexagonal numbers (A000384).at n=3A046177
• Numbers that are n-gons for three or more n's, where n=3,4,5,...,16.at n=27A062712
• Nontrivial binomial coefficients which are perfect powers (A001597).at n=6A075760
• Smallest triangular number with exactly n divisors, or 0 if no such number exists.at n=14A081978
• Square numbers which equal a triangular number times an odd number between 1 and 15.at n=27A094973
• Sum of the areas of the first n+1 Pell triangles.at n=13A096979
• Numbers which are powerful(1) (A001694) and triangular at the same time.at n=8A113938
• Triangle T(n, k, m) = b(n,m)/(b(k,m)*b(n-k,m)), where b(n, k) = Product_{j=1..n} (1 - ChebyshevT(j, k+1)^2), b(n, 0) = n!, and m = 2, read by rows.at n=29A156645
• Triangle T(n, k, m) = b(n,m)/(b(k,m)*b(n-k,m)), where b(n, k) = Product_{j=1..n} (1 - ChebyshevT(j, k+1)^2), b(n, 0) = n!, and m = 2, read by rows.at n=34A156645
• A204512(n)^2 = floor[A055872(n)/8]: Squares such that appending some digit in base 8 yields another square.at n=15A204504
• Square triangular numbers that can be expressed as sums of a positive square number and a positive triangular number. Intersection of A182427 and A214937.at n=3A218273
• Square triangular numbers that are the sum of 2 nonzero nonconsecutive triangular numbers.at n=3A267297
• Table read by rows: T(n,k) is the smallest triangular number that begins a run of exactly k consecutive triangular numbers with n divisors, or 0 if no such run exists.at n=17A319038
• Smallest triangular number whose number of divisors is the n-th triangular number, or 0 if no such number exists.at n=4A323747