33670

Appears in sequences

• Numbers k that, when expressed in base 5 and then interpreted in base 8, give a multiple of k.at n=40A062930
• Triangular numbers which are also happy numbers (cf. A007770).at n=40A076712
• a(n) = A052217(n)/3.at n=42A088405
• Partial sums of dodecahedral numbers (A006566).at n=13A116689
• a(n) = 1 + n + binomial(n+3,5).at n=20A154322
• The positions of zeros in A163898 and A163899.at n=36A165403
• Rectangular array T(n,k) = binomial(n+1,2)*(n^k - (n-1)^k) read by antidiagonals.at n=39A178831
• Triangular numbers that are hypotenuse and a leg of a Pythagorean triple.at n=35A213188
• Number of all possible tetrahedra of any size, having reverse orientation to the original regular tetrahedron, formed when intersecting the latter by planes parallel to its sides and dividing its edges into n equal parts.at n=38A216172
• G.f.: (1+8*x+22*x^2+8*x^3+x^4)/(1-x)^6.at n=9A220892
• Degeneracies of entanglement witness eigenstates for 2n spin 9/2 irreducible representations.at n=4A272394
• The first of three consecutive triangular numbers the sum of which is equal to the sum of three consecutive primes.at n=21A298168
• a(1) = 8; for n > 1, a(n) is the largest integer m such that m = ((2*x*a(n-1)) / (x+1)) - x, with x a positive nontrivial divisor of m.at n=18A338026
• Triangular numbers such that the sum of cubes of their digits is prime.at n=16A345351
• For 1<=x<=n, 1<=y<=n with gcd(x,y)=1, write 1 = gcd(x,y) = u*x+v*y with u,v minimal; a(n) = m^2*s, where s is the population variance of the values of u+v and m is the number of such values.at n=12A345725
• Triangular numbers which are products of five distinct primes.at n=11A357590