31025

Appears in sequences

• a(n) is the number of integers m which take n steps to reach 1 in '3x+1' problem.at n=46A005186
• Numbers that are the sum of 2 nonzero squares in exactly 6 ways.at n=26A025289
• Numbers that are the sum of 2 nonzero squares in 6 or more ways.at n=27A025297
• Numbers that are the sum of 2 distinct nonzero squares in exactly 6 ways.at n=26A025307
• Numbers that are the sum of 2 distinct nonzero squares in 5 or more ways.at n=34A025315
• Numbers that are the sum of 2 distinct nonzero squares in 6 or more ways.at n=27A025316
• Sum of determinants of 2nd order principal minors of powers of inverse of the matrix ((1,1,0,0),(1,0,1,0),(1,0,0,1),(1,0,0,0)).at n=21A074453
• Numbers m that are the hypotenuse of exactly 22 distinct integer-sided right triangles, i.e., m^2 can be written as a sum of two squares in 22 ways.at n=27A097103
• Primitive subsequence of A111105.at n=41A137559
• Number of binary strings of length n with no substrings equal to 0010 0110 or 1101.at n=18A164499
• Number of isomorphism classes of nanocones with 5 pentagons and a symmetric boundary of length n.at n=15A198086
• Numbers n such that prime(n) + reversal(prime(n)) is a square.at n=29A227371
• a(n) = Sum_{k=0..3} f(n+k)^2 where f=A130519.at n=26A238604
• Number of 8-digit positive integers in base n where the sum of the first k digits equals the sum of the last k digits.at n=3A240928
• Numbers n such that the decimal number concat(7,n) is a square.at n=35A273362
• Numbers with property that both the digit sum and the sum of the prime factors (counted with multiplicity) have only digits 0 and 1 in base 10.at n=21A297614