22130

Appears in sequences

• a(n) = a(1) + a(2) + ... + a(n-1) + a(m) for n >= 4, where m = n - 1 - 2^p and p is the unique integer such that 2^p < n - 1 <= 2^(p+1), with a(1) = 1, a(2) = 2, and a(3) = 1.at n=15A049950
• Numbers such that the digital sum base 2 and the digital sum base 3 and the digital sum base 10 all are equal.at n=22A135120
• Expansion of Product_{k>=1} ((1+x^k) / ((1-x^(2*k-1)) * (1-x^(8*k-4)))).at n=29A280908
• Let m(k) be the index of the largest triangular number <= k; then a(n) is the smallest number k that can be written as the sum of three triangular numbers if the largest is the (m(k)-n)-th triangular number, but no larger.at n=14A331753
• Numbers that cannot be expressed as the sum of one or more numbers without any repeated digits.at n=10A342080
• a(n) = A068346(A276086(n)), where A068346 is the second arithmetic derivative, and A276086 is the primorial base exp-function.at n=53A370131
• a(n) is the integer part of the area of a regular n-gon whose side lengths are n.at n=20A374296