18081

Appears in sequences

• Numbers with mirror symmetry about middle.at n=23A006072
• a(n) = (2*n - 1)*n^2.at n=21A015237
• Palindromic Super-2 Numbers.at n=29A032750
• Palindromic and divisible by 9.at n=31A045644
• Palindromes with exactly 5 prime factors (counted with multiplicity).at n=23A046331
• Composite palindromes whose sum of prime factors is prime (counted with multiplicity).at n=41A046365
• Number of n X n 0..8 matrices with all row and column sums equal.at n=3A067216
• Numbers n such that n and 2n+1 are both palindromes.at n=43A069881
• Numbers n for which there are exactly nine k such that n = k + reverse(k).at n=33A072433
• a(n) = floor(average of first n cubes).at n=40A078618
• Least k such that 10^n+k is a brilliant number (cf. A078972).at n=6A083289
• a(n) = ceiling((sqrt n)^(sqrt n)).at n=31A094093
• Triangular matrix, read by rows, that satisfies: T(n,k) = [T^2](n-1,k) when n>k>=0, with T(n,n) = (2*n+1).at n=24A102320
• Numbers that cannot be expressed as a sum of 2 triangular numbers and a power of 2.at n=1A112665
• Palindromic numbers that contain the sum of their digits as a substring.at n=21A121939
• Row sums of A128623.at n=40A128624
• Integers k such that 10^k + 61 is a prime number.at n=14A135116
• Palindromic cyclops numbers.at n=17A138131
• Strobogrammatic cyclops numbers.at n=7A153806
• Integer averages of the first perfect cubes up to some n^3.at n=30A164577