81810

Appears in sequences

• Multiplicity of highest weight (or singular) vectors associated with character chi_66 of Monster module.at n=43A034454
• Triangular numbers with property that digits alternate in parity individually as well as in concatenation with previous terms.at n=23A068889
• Non-palindromic numbers such that either x=q1.Rev[x] or Rev[x]=q2.x, where R[x]=A004086[x] and q1 or q2 are integers not divisible by 10.at n=30A071687
• Triangular numbers whose sum of prime factors (with repetition) is also triangular.at n=33A076169
• Triangular numbers which are 7-almost primes.at n=25A076581
• Triangular numbers all of whose digits are nonprimes.at n=36A111484
• Triangular numbers for which the sum of the digits equals the sum of the digits of the next triangular number.at n=19A117511
• Triangular numbers composed of digits {0,1,8}.at n=5A119045
• Triangular numbers which are sums of 6 consecutive primes.at n=9A173423
• Let i be in {1,2,3,4} and let r >= 0 be an integer. Let p = {p_1, p_2, p_3, p_4} = {-2,0,1,2}, n=3*r+p_i, and define a(-2)=0. Then a(n)=a(3*r+p_i) gives the quantity of H_(9,2,0) tiles in a subdivided H_(9,i,r) tile after linear scaling by the factor Q^r, where Q=sqrt(x^2-1) with x=2*cos(Pi/9).at n=42A187500
• Triangular numbers n such that each decimal digit of n is equal to the difference of at least two other digits of n.at n=13A255917
• Call n/m a superdivisor of n if n/m + n divides (n/m)^(n/m) + n, (n/m)^n + n/m and n^(n/m) + n/m. This sequence gives the smallest number with n superdivisors.at n=4A272538
• Numbers that are not palindromes even after removing trailing zeros and are divisible by their reverses.at n=39A345361
• a(n) is the largest number in row n of A380920.at n=44A380967