15040
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 10
- Digital Root
- 1
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 28
- Divisor Sum
- 36576
- Proper Divisor Sum (Aliquot Sum)
- 21536
- Abundant Number
- yes
- Perfect Number
- no
- Deficient Number
- no
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 5888
- Möbius Function
- 0
- Radical
- 470
- Omega Function (Ω)
- 8
- Little Omega Function (ω)
- 3
Special
- Factorial
- no
- Catalan Number
- no
- Bell Number
- no
- Motzkin Number
- no
- Primorial
- no
Figurate Numbers
- Fibonacci Number
- no
- Triangular Number
- no
- Perfect Square
- no
- Perfect Cube
- no
- Pentagonal Number
- no
- Hexagonal Number
- no
- Lucas Number
- no
- Tetrahedral Number
- no
- Pell Number
- no
- Tribonacci Number
- no
- Pronic Number
- no
Recreational
- Happy Number
- no
- Harshad Number
- yes
- Narcissistic Number
- no
- Collatz Steps
- 133
- Smith Number
- no
- Vampire Number
- no
Primality
- Prime
- no
- Composite Number
- yes
- Semiprime
- no
- Squarefree Number
- no
- Prime Power
- no
- Prime Factorization
- no
- Twin Prime
- no
- Mersenne Prime
- no
- Sophie Germain Prime
- no
- Safe Prime
- no
- Powerful Number
- no
- Achilles Number
- no
- Perfect Power
- no
- Smooth Number
- no
- Carmichael Number
- no
Classification
- Even
- yes
- Odd
- no
Appears in sequences
- Cluster series for square lattice.at n=13A003203
- Expansion of Product_{m>=1} (1-m*q^m)^32.at n=5A022692
- Expansion of (theta_3(z)*theta_3(5z)+theta_2(z)*theta_2(5z))^4.at n=29A028589
- Theta series of 10-dimensional 2-modular lattice of minimal norm 2.at n=9A029545
- Theta series of odd 8-dimensional 5-modular lattice O(5).at n=29A029719
- Numbers k such that the continued fraction for sqrt(k) has even period and if the last term of the periodic part is deleted the central term is 61.at n=28A031559
- McKay-Thompson series of class 25A for Monster.at n=29A058594
- Bisection of Lucas triangle A060922: odd-indexed members of column sequences of A060922 (not counting leading zeros).at n=23A060924
- Second convolution of Lucas numbers A000032(n+1), n >= 0.at n=9A060929
- Third column of Lucas bisection triangle (odd part).at n=4A061172
- a(n) = n*(n+7)*(n+8)/6.at n=40A111396
- Let M0 = {{2, 2, 0}, {1, 0, 1}, {0, 2, 2}}; M1 = {{1, 0, 1}, {2, 2, 0}, {0, 2, 2}}; M2 = {{2, 2, 0}, {0, 2, 2}, {1, 0, 1}}; M[n_] := M[n] = If[Mod[v[n][[1]], 3] == 0, M1, If[Mod[v[n][[2]], 3] == 0, M0, M2]] v[0] = {1, 1, 1}; M[0] = {{2, 2, 0}, {1, 0, 1}, {0, 2, 2}}; v[n_] := v[n] = M[n - 1].v[n - 1]. Then a(n) =v[n][[1]].at n=8A115106
- Triangle read by rows: row n is the first row of the matrix M[n]^(n-1), where M[n] is the n X n tridiagonal matrix with main diagonal (2,4,4,...) and super- and subdiagonals (1,1,1,...).at n=30A124575
- 5 times octagonal numbers: a(n) = 5*n*(3*n-2).at n=32A153795
- Indices of the least triangular numbers (A000217) for which three consecutive triangular numbers sum to a perfect square (A000290).at n=8A165517
- Partial sums of A048995.at n=46A174514
- Number of 4-step one space for components leftwards or up, two space for components rightwards or down asymmetric quasi-bishop's tours (antidiagonal moves become knight moves) on an n X n board summed over all starting positions.at n=19A187608
- Number of n X 2 0..4 arrays with each element x equal to the number its horizontal and vertical neighbors equal to 3,0,1,2,4 for x=0,1,2,3,4.at n=8A196212
- T(n,k)=Number of nXk 0..4 arrays with each element x equal to the number of its horizontal and vertical neighbors equal to 3,0,1,2,4 for x=0,1,2,3,4.at n=46A196218
- T(n,k)=Number of nXk 0..4 arrays with each element x equal to the number of its horizontal and vertical neighbors equal to 4,0,1,2,3 for x=0,1,2,3,4.at n=46A196685