729729

Appears in sequences

• Odd abundant numbers not divisible by 5.at n=16A064001
• Smallest number having n divisors ending with 1 or 9.at n=27A085645
• Expansion of g.f. c(3x)^3, where c(x) is the g.f. of A000108.at n=6A101601
• Riordan array (1, x*c(3x)), c(x) the g.f. of A000108.at n=48A110518
• a(n) = 3^5 * binomial(n+4, 5).at n=10A113335
• a(n) = binomial(n+10, 10)*3^n.at n=5A172362
• a(n) = concatenation of n^3 with itself.at n=8A175605
• 3^n concatenated with itself.at n=6A206527
• a(n) = concatenation of n^2 with itself.at n=26A253445
• G.f. A(x) satisfies: A(x - 3*x^3) = 1/(1 - 3*x).at n=10A276368
• Smallest number having exactly n divisors ending with 3 or 7.at n=27A331082
• Numbers that are the concatenation of a square and a cube, and also the concatenation of a cube and a square.at n=27A363835
• Odd abundant numbers that are also doublets (cf. A020338).at n=34A380232
• Odd abundant numbers not divisible by 5 that are also doublets (cf. A020338).at n=13A380233