2205225

Appears in sequences

• Squares of odd triangular numbers.at n=27A014736
• Expansion of 1/((1-3x)(1-6x)(1-9x)).at n=6A017933
• Squares composed of digits {0,2,5}, not ending with zero.at n=7A058426
• Squares that are the concatenation of three numbers, one of which is the sum of the other two.at n=21A062555
• Stirling2 triangle with scaled diagonals (powers of 3).at n=38A075498
• Odd abundant numbers whose abundance is odd.at n=9A156942
• Number of arrays of -2..2 integers x(1..n) with every x(i) in a subsequence of length 1, 2, 3 or 4 with sum zero.at n=10A193704
• Number of 4Xn 0..1 arrays avoiding 0 0 1 and 0 1 1 horizontally and 0 0 1 and 1 0 1 vertically.at n=15A208143
• Perfect squares k such that each decimal digit of k is equal to the difference of at least two other digits of k.at n=30A255893
• Number of (n+1)X(3+1) arrays of permutations of 0..n*3-1 with each element moved a city block distance of exactly 2.at n=3A263387
• Number of (n+1)X(4+1) arrays of permutations of 0..n*4-1 with each element moved a city block distance of exactly 2.at n=2A263388
• T(n,k)=Number of (n+1)X(k+1) arrays of permutations of 0..n*k-1 with each element moved a city block distance of exactly 2.at n=17A263389
• T(n,k)=Number of (n+1)X(k+1) arrays of permutations of 0..n*k-1 with each element moved a city block distance of exactly 2.at n=18A263389
• Odd abundant numbers k for which sigma(k) == 3 (mod 4).at n=6A325311
• Odd numbers k such that sigma(k) > 2*k and A003415(sigma(k)) < k, where A003415 is the arithmetic derivative, and sigma is the sum of divisors function.at n=3A347890
• Obverse convolution (n(n+1)/2)**(n(n+1)/2); see Comments.at n=5A375050