24842

Appears in sequences

• Generating function = Product_{m>=1} 1/(1 - x^m)^2; a(n) = number of partitions of n into parts of 2 kinds.at n=20A000712
• Numbers k such that the continued fraction for sqrt(k) has period 49.at n=29A020388
• Palindromes with exactly 2 palindromic prime factors (counted with multiplicity), and no other prime factors.at n=31A046376
• Palindromes with exactly 2 distinct palindromic prime factors.at n=27A046408
• Numbers k such that the first k ternary digits found in the decimal expansion of Pi form a prime.at n=5A065570
• Palindromic integers > 0, whose 'Reverse and Add!' trajectory (presumably) does not lead to another palindrome.at n=11A070001
• a(1)=1, a(n) is the smallest integer > a(n-1) such that the sum of elements of the simple continued fraction for S(n)=1/a(1)+1/a(2)+...+1/a(n) equals n*(n+1)/2 the n-th triangular number.at n=28A071184
• Numbers n for which there are exactly ten k such that n = k + reverse(k).at n=26A072434
• Palindromic even squarefree numbers with an even number of distinct prime factors.at n=25A075811
• Palindromic even numbers with exactly 2 prime factors (counted with multiplicity). Equivalently, palindromic numbers of the form 2*p with p prime.at n=18A075813
• Number of partitions of 2*n into parts of two kinds.at n=10A100534
• Number of n X 3 0..2 arrays with rows, diagonals and antidiagonals unimodal and columns nondecreasing.at n=6A224257
• T(n,k) = number of n X k 0..2 arrays with rows, diagonals and antidiagonals unimodal and columns nondecreasing.at n=42A224262
• Number of 7 X n 0..2 arrays with rows, diagonals and antidiagonals unimodal and columns nondecreasing.at n=2A224267
• Conjectured record-breaking numbers of odd elements, for ascending positive integers k, in primitive cycles of positive integers under iteration by the Collatz-like 3x+k function.at n=31A226673
• Numbers k such that (7*10^k + 179)/3 is prime.at n=28A271506
• a(n) = A273059(4n+2).at n=27A275918
• Numbers k such that 5*10^k - 13 is prime.at n=23A294131
• Exponential Demlo sequence, like 12345...54321, but for powers of 2 instead.at n=2A309037
• Numbers k such that there are exactly four biquadratefree powerful numbers (A338325) between k^2 and (k+1)^2.at n=20A338391