40755

Appears in sequences

• Exponential convolution of Fibonacci numbers with themselves (divided by 2).at n=11A014335
• Numbers that are both triangular and pentagonal.at n=3A014979
• "DHK[ 8 ]" (bracelet, identity, unlabeled, 8 parts) transform of 1,1,1,1,...at n=16A032249
• Hexagonal pentagonal numbers.at n=1A046180
• Odd numbers with exactly 5 distinct prime factors.at n=12A046391
• Numbers n such that the cyclotomic polynomial of order n has a nonzero coefficient which does not appear in any cyclotomic polynomials of lower order.at n=19A046887
• Number of nonempty subsets of {1,2,...,n} in which exactly 2/3 of the elements are <= (n-4)/2.at n=21A048062
• a(n) = n*(n^2 - 1)*(n + 2)*(n^2 + 4*n + 6)/72.at n=11A054563
• a(n) = Sum_{i=1..n} Sum_{j=1..i} (prime(i) - prime(j)).at n=37A062020
• Numbers that are n-gons for three or more n's, where n=3,4,5,...,16.at n=11A062712
• Triangular numbers with sum of digits = 21.at n=26A068131
• Triangular numbers which are products of triangular numbers larger than 1.at n=32A068143
• Triangular numbers that are one-third of another triangular number: T(m) such that 3*T(m) = T(k) for some k.at n=5A076139
• Triangular numbers with square pyramidal indices.at n=9A076767
• Third row of Pascal-(1,6,1) array A081581.at n=41A081591
• Row 8 of array in A288580.at n=19A092973
• 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=22A095877
• a(n) = (n+1)*(n+2)^2*(n+3)*(n+4)*(n+5)*(2*n+3)/720.at n=8A108681
• Partial products of primes with primitive root 2.at n=4A108975
• Triangular numbers for which the sum of the digits is an octagonal number.at n=29A117523