37401

Appears in sequences

• Triangular numbers whose digit permutations yield at least two further triangular numbers.at n=22A069674
• Rearrangement of triangular numbers such that the sum of two consecutive terms is a palindrome.at n=40A082980
• Indices of primes in sequence defined by A(0) = 59, A(n) = 10*A(n-1) - 71 for n > 0.at n=12A101572
• Hexagonal numbers for which the sum of the digits is also a hexagonal number.at n=30A117062
• Hexagonal numbers for which both the sum of the digits and the product of the digits are also hexagonal numbers.at n=17A117064
• Hexagonal numbers with prime indices.at n=32A117961
• Triangular numbers of the form 2p-1 where p is prime.at n=35A217000
• Triangular numbers which have one or more occurrences of exactly five different digits.at n=26A241788
• Triangular numbers T such that both (T+2) and (T-2) are semiprimes.at n=39A242356
• Triangular numbers n with digits d_1, d_2, ..., d_k such that d_1*(d_1+1)/2 + ... + d_k*(d_k+1)/2 is a triangular number.at n=33A254957
• a(n) = n*(n + 1)*(n + 2)*(n + 3)*(n^2 - n + 5)/120.at n=11A256860
• Numbers k such that k!! - 1024 is prime.at n=18A258866
• Convolution of nonzero triangular numbers (A000217) and nonzero tetradecagonal numbers (A051866).at n=11A271567
• Expansion of 1 - 1/Sum_{k>=0} k!!*x^k.at n=13A307064
• Main diagonal of A323212.at n=6A323216
• Composite numbers k such that P(k, 7) == 7 (mod k), where P(k, 7) = A084768(k) is the k-th Legendre polynomial evaluated at 7.at n=20A330205
• a(n) = (m(n)^2 + 3)*(m(n)^2 + 7)/32, where m(n) = 2*n - 1.at n=16A336535
• Hexagonal numbers that are products of exactly four distinct primes.at n=22A381920