18751

Appears in sequences

• Trimorphic numbers: n^3 ends with n. Also m-morphic numbers for all m > 5 such that m-1 is not divisible by 10 and m == 3 (mod 4).at n=37A033819
• Sums of 3 distinct powers of 5.at n=30A038475
• Trimorphic but not bimorphic nor automorphic.at n=28A056032
• Numbers k such that k^4 == 1 (mod 5^5).at n=24A056102
• Denominators of convergents to Pi by Farey fractions.at n=33A063673
• Least m ending in 1 such that m^n ends in a string of n 0's followed by the final 1.at n=3A085610
• Numbers k such that k-1 and k+1 are each the product of exactly 7 primes, counted with multiplicity.at n=3A157487
• a(n) = 625*n + 1.at n=29A158383
• a(n) = 30*n^2 + 1.at n=25A158558
• Smallest number m > 1 such that m^2 == 1 (mod 10^n).at n=4A181539
• Numbers n with k digits such that n^2 == 1 (mod 10^k).at n=19A181607
• a(n) = 6*5^n+1.at n=5A199216
• Number of (w,x,y,z) with all terms in {1,...,n} and w<average{x,y,z}.at n=14A212088
• Numbers whose squares have 2R-1 digits, such that the number represented by leftmost R digits and number represented by rightmost R digits divide each other evenly.at n=16A216233
• (2*16^(5^n) - 1) mod 10^n: a sequence of trimorphic numbers ending in 1.at n=4A224474
• Numbers k such that Sum_{i=1..k} sigma(i)^d(i) == 0 (mod k), where sigma = A000203 and d = A000005.at n=15A260654
• Numbers n such that n^2 = a^2 + b^5 (with integers a, b > 0) and gcd(a, b, n) = 1.at n=19A293284
• a(n) is the first semiprime k such that k-1 and k+1 each have exactly n prime factors (counted with multiplicity).at n=6A365537
• Numbers m such that m^m == m (mod 10^(len(m) + 2)), where len(m) is the number of digits of m (A055642).at n=15A373206
• Number of subsets of {1,2,...,n} such that no two elements differ by 1 or 5.at n=23A374737