22715

Appears in sequences

• Truncated square pyramid numbers: a(n) = Sum_{k = n..2*n} k^2.at n=21A050409
• Sum of squares of numbers that cannot be written as t*p(n) + u*p(n+1) for nonnegative integers t,u, where p(n) is the n-th prime.at n=3A076430
• If S*2^k - 3 and S*2^k + 3 are primes for k=0 to 2, then a(n) = S/10.at n=4A093290
• Numbers n such that the middle coefficient of the cyclotomic polynomial Phi_n(x) has a value not obtained for any smaller n.at n=15A095877
• a(n) = Sum_{m=1..n} A000045(m)*(A004001(m+1) - 2*A004001(m) + A004001(m-1)).at n=23A120475
• Numbers k such that k and k^2 use only the digits 1, 2, 5, 7 and 9.at n=14A137009
• a(n) = (6 + 10*n + 5*n^2 + n^3)/2.at n=34A164845
• Partial sums of A000132.at n=28A175360
• Number of nX3 arrays of the minimum value of corresponding elements and their horizontal or antidiagonal neighbors in a random, but sorted with lexicographically nondecreasing rows and columns, 0..2 nX3 array.at n=6A219622
• T(n,k)=Number of nXk arrays of the minimum value of corresponding elements and their horizontal or antidiagonal neighbors in a random, but sorted with lexicographically nondecreasing rows and columns, 0..2 nXk array.at n=42A219627
• Number of 7Xn arrays of the minimum value of corresponding elements and their horizontal or antidiagonal neighbors in a random, but sorted with lexicographically nondecreasing rows and columns, 0..2 7Xn array.at n=2A219633
• The least k such that the polynomial cyclotomic(k,x) has n different coefficients.at n=22A231611
• a(n) is the smallest number k such that n*k is a partition number.at n=16A235704
• Number of distinct parabolic double cosets of the symmetric group S_n.at n=5A260700
• Number of orbits of Aut(Z^7) as function of the infinity norm n of the representative lattice point of the orbit, when the cardinality of the orbit is equal to 80640.at n=22A266396
• Numbers k such that (38*10^k + 403)/9 is prime.at n=16A295624
• Numbers k such that 8k+1, 12k+1 and 24k+1 are primes and the last two are also of the form x^2 + 27y^2, so the tetrahedral number T(24k+1) is a Fermat pseudoprime to base 2.at n=16A321867
• First occurrence of n in A345079, or -1 if n does not occur in A345079.at n=22A345080
• Expansion of Sum_{1<=i<=j} q^(i+j)/( (1-q^i)*(1-q^j) )^2.at n=41A374929