176418

Appears in sequences

• Number of primitive (aperiodic) palindromes using a maximum of three different symbols.at n=21A056459
• Number of walks within N^3 (the first octant of Z^3) starting at (0,0,0) and consisting of n steps taken from {(-1, 0, 0), (1, 0, 0), (1, 0, 1), (1, 1, 0)}.at n=9A151162
• Averages of twin prime pairs k such that k*2 and k/2 are squares.at n=16A154670
• Numbers k that divide A000201(k)^m for some integer m > 0, where A000201 is the lower Wythoff sequence.at n=38A185615
• Monotonic ordering of nonnegative differences 3^i-9^j, for 40>=i>=0, j>=0.at n=33A192157
• Numbers n for which n*n'/(n+n') is an integer, where n' is the arithmetic derivative of n.at n=37A210935
• Number of non-palindromic n-tuples of 3 distinct elements.at n=10A242278
• Numbers k whose bi-unitary divisors have an even sum which is larger than 2k, but they cannot be partitioned into two disjoint parts whose sums are equal.at n=19A323342
• a(n) is the conjectured largest number such that both a(n) and a(n) - n are 11-smooth numbers, or 0 if no such number exists. a(n) can be less than n.at n=17A392256