2000001

Appears in sequences

• Numbers k such that k^2+k+2 is a palindrome.at n=31A027712
• Numbers whose square contains the same digit more than 2/3 of the time and does not end in 0.at n=21A039820
• Numbers k such that k^2 contains only digits {0,1,4}, not ending with zero.at n=22A058413
• a(n) = sqrt(A077204(n)).at n=12A077205
• a(1) = 2, then the smallest squarefree number greater than the previous term that begins with the end of the previous term.at n=16A077209
• a(1) = 1 and a(n+1) is the least number > a(n) that begins with the last digit of a(n) and doesn't end with 0.at n=18A098752
• Lexicographically earliest increasing sequence whose k-th digit is the absolute difference between the two digits touching the k-th comma.at n=22A102663
• Numbers n such that n + phi(n) is a repdigit.at n=21A116018
• Numbers n with property that average digit of n^2 is less than 1.at n=25A164842
• Sum of any three adjacent digits of n^2 is a square.at n=53A174397
• a(n) = 2*10^n + 1.at n=6A199682
• Numbers whose English name requires fewer letters than twice the number of decimal digits.at n=7A235029
• In base 3, 0, together with numbers of the form i00j00k00m00... where i = 1 or 2 and j,k,m,... are 0, 1, or 2.at n=35A261660
• Variation on Golomb's sequence starting with (1,2): a(n)=length of n-th run of both consecutive integers and consecutive digits with same parity.at n=10A327143
• Lexicographically earliest sequence of nonnegative terms forming a clockwise square spiral when nothing else is read except the parity of the digits or the parity of the terms (see the Comments section).at n=30A341903
• The lexicographically earliest "Increasing Term Fractal Jump Sequence".at n=12A359611
• Ternary numbers consisting of a run of 2's, then a run of 0's, then a run of 1's.at n=20A371057
• Ternary numbers that are concatenated runs C(1)B(1)A(1)C(2)B(2)A(2)...C(k)B(k)A(k), where A(i) is a run of 1's, B(i) a run of 0's, and C(i) a run of 2's, for i = 1..k.at n=21A371109