61600

Appears in sequences

• a(n) is least k such that k and 2k are anagrams in base n (written in base 10).at n=18A023094
• Number of reversible strings with n-1 beads of 2 colors. 4 beads are black. String is not palindromic.at n=38A032091
• a(0)=1; a(n) = sigma_1(n) + sigma_3(n).at n=39A092345
• Numbers k not divisible by 6 such that sigma(k) > 3*k.at n=1A126104
• Triangle T, read by rows, where T(n,k) = A008544(n-k)*C(n,k) where A008544 equals the triple factorials in column 0.at n=40A136216
• Long leg B of primitive Pythagorean triangles such that perimeters are Averages of twin prime pairs, q=p+1, a=q^2-p^2, c=q^2+p^2, b=2*p*q, s=a+b+c, s-+1 are primes.at n=17A155174
• Denominator of Laguerre(n, -3).at n=11A160614
• Number of binary strings of length n with equal numbers of 0011 and 1100 substrings.at n=17A164175
• Numbers with prime factorization pqr^2s^5.at n=31A190293
• Number of ordered triples (w,x,y) with all terms in {-n,...-1,1,...,n} and w+x+y>0.at n=25A211545
• Number of free tree-like 4d-polycubes of size n.at n=8A304198
• Lesser of amicable pair m < n defined by t(n) = m and t(m) = n where t(n) = psi(n) - n and psi(n) = A001615(n) is the Dedekind psi function.at n=25A323329
• Numbers k with property that k is the least logarithmically smooth numbers (meaning largest prime factor of k is less than log(k)) having squarefree kernel equal to squarefree kernel of k.at n=19A333961
• a(n) = n!/d where d is the maximum divisor of n! with equal prime exponents.at n=12A336619
• Numbers that cannot be expressed as sum of at most nine repdigits numbers. One may not add two integers with the same repeated digit.at n=15A339673
• a(n) is the least number with exactly n divisors of the form 3*k+1.at n=35A364582
• a(n) is the least number with exactly n divisors of the form 3*k+2.at n=36A364583
• Obverse convolution A000045**A000032; see Comments.at n=5A374865