19481

Appears in sequences

• 4-dimensional pyramidal numbers: a(n) = n^2*(n^2-1)/12.at n=22A002415
• Numerator of n*(n-3)*(3*n^2-6*n+2)/(3*(n-1)*(n-2)).at n=11A023417
• a(n) = (3*n+1)*(4*n+1).at n=40A033577
• Truncated triangular pyramid numbers: a(n) = (n-7)*(n^2 + 10*n - 108)/6, n >= 8.at n=41A051941
• a(n) = (n/2)*(n + 1)*(3*n + 11).at n=21A059997
• a(n) = (2*n-1)*(13*n^2-13*n+6)/6.at n=16A063493
• Numbers k such that gcd(3k,8^k+1) = 3 but k does not divide the numerator of B(2k) (the Bernoulli numbers).at n=29A070193
• An interleaved sequence of pyramidal and polygonal numbers.at n=42A081283
• Row sums of triangle A086612.at n=9A086613
• a(n) = (2/(n-1))*a(n-1) + ((n+5)/(n-1))*a(n-2) with a(0)=0 and a(1)=1.at n=41A096338
• Fifth column (m=4) of (1,6)-Pascal triangle A096956.at n=20A096958
• Sum of numbers under a triangle on a spiral staircase of width 10.at n=20A111080
• One fifth of the sum of the first n primes, when an integer.at n=31A112271
• A002415 and A052472 interlaced.at n=43A117651
• Multiples of 23 whose digit reversal + 1 is also a multiple of 23.at n=34A166393
• a(n) = a(n-1)+a(n-2)+a(n-3)+4*n-8 with a(0)=0, a(1)=0 and a(2)=1.at n=15A180668
• a(n) = n^2 * (4*n^2 - 1) / 3.at n=11A187756
• Number of lower triangles of a 3 X 3 0..n array with each element differing from all of its diagonal, vertical, antidiagonal and horizontal neighbors by two or less.at n=19A195249
• Numbers n such that n^10+10 is prime.at n=32A239347
• Number of partitions of n with difference 8 between the number of odd parts and the number of even parts, both counted without multiplicity.at n=38A242699