61075

Appears in sequences

• Numbers k such that k | 7^k + 7.at n=35A015893
• Strong pseudoprimes to base 51.at n=28A020277
• Odd triangular numbers with prime indices.at n=33A034954
• a(1) = 1; a(n) is the smallest triangular number > a(n-1) which differs from it at every digit.at n=33A068855
• Number of polyiamonds with n cells that do not tile the plane.at n=14A071333
• a(1) = 1, a(n+1)= smallest triangular number greater than the n-th partial sum.at n=15A076971
• Triangular numbers p*(p+1)/2 with p prime such that 1+(number of prime factors of p+1) is prime.at n=29A144549
• Number of walks within N^2 (the first quadrant of Z^2) starting at (0,0), ending on the vertical axis and consisting of n steps taken from {(-1, -1), (-1, 0), (-1, 1), (0, 1), (1, -1), (1, 0)}.at n=9A151468
• Cyclops triangular numbers.at n=14A160717
• Numbers n which are concatenations n=x//y such that x^2+y^3 is a multiple of n.at n=42A162464
• a(n) = n*(n+1)*(9*n^2 - n - 5)/6.at n=14A172075