39903

Appears in sequences

• Leading term of Stirling's approximation to n!, sqrt(2*Pi)*n^(n+(1/2))/e^n, rounded up.at n=8A005395
• Triangular numbers which are a concatenation of two or more positive triangular numbers.at n=37A068144
• Triangular numbers with internal digits also forming a triangular number.at n=36A069702
• Number of compositions of n into twin primes (i.e., primes that are members of a twin prime pair, like 3, 5, 7, 11, 13, but not 2 or 23).at n=47A077608
• Triangular numbers using only the curved digits 0, 3, 6, 8 and 9.at n=14A079653
• a(n) = p(n)*(p(n)-1)/2 where p(n) = upper member of n-th pair of twin primes.at n=18A082669
• Triangular numbers with palindromic indices.at n=37A089717
• Triangular numbers composed of digits {0,3,9}.at n=6A119069
• 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=8A255917
• Triangular numbers representable as x*y+x+y such that x and y are triangular numbers, x>=y>0.at n=23A259745
• Triangular numbers representable as x*y+x+y such that x and y are triangular numbers, x>=y>1.at n=18A259746
• The first of three consecutive triangular numbers the sum of which is equal to the sum of three consecutive primes.at n=22A298168
• Number of ways to split a strict integer partition of n into consecutive subsequences with strictly decreasing sums.at n=48A318684
• Integers m such that A342805(m) = m+3.at n=28A342806