81818

Appears in sequences

• Numbers with mirror symmetry about middle.at n=31A006072
• Number of triangulated (n+2)-gons rooted at an exterior edge.at n=10A006078
• Numbers k such that the least term in the periodic part of the continued fraction for sqrt(k) is 26.at n=21A031704
• Base 10 palindromes that start with 8.at n=40A043043
• Numbers whose consecutive digits differ by 7.at n=28A048409
• Expansion of (8+10*x)/((1-x)*(1-100*x)).at n=2A097818
• Numbers k such that k * (k+1) is the concatenation of a number m with itself.at n=5A116285
• a(n) = 676*n^2 + 2*n.at n=10A158385
• a(n) = 484*n^2 + 22.at n=13A158629
• a(n) = 169*n^2 + n.at n=21A173275
• Palindromic numbers which are sum of consecutive squares.at n=39A180436
• Palindromic numbers which can be written as the sum of two or more consecutive squares.at n=27A216446
• Numbers k of the form a - b + c, such that k^3 equals the decimal concatenation a//b//c and numbers k, b, and c have the same number of digits.at n=20A259379
• Starts of runs of 3 consecutive lazy-tribonacci-Niven numbers (A352107).at n=10A352109