20313

Appears in sequences

• Numbers n such that n and n-1 are differences between 2 positive cubes in at least one way.at n=19A038595
• Numbers n such that (i) the largest prime factor of n is not a palindrome and (ii) the sum of the factorials of the digits of n is equal to the largest prime factor of n reversed.at n=12A074301
• Let f(k) denote the largest prime factor of k which is not a palindrome. Sequence gives numbers k such that the sum of the factorials of the digits of k is equal to f(k) reversed.at n=12A111185
• Terms of A110566 grouped.at n=62A112811
• Expansion of 3 * q^(1/3) * phi(q) * psi(q^6) / c(q) in powers of x where phi(), psi() are Ramanujan theta functions and c() is a cubic AGM theta function.at n=37A233037
• Expansion of Product_{n>=1} (1 - x^(5*n))/(1 - x^n)^3 in powers of x.at n=14A278668
• Numbers of the form HMMSS with primes H < 24 and MM, SS < 60, for which the number of seconds after midnight, 3600*H+60*MM+SS, is also prime.at n=4A295011
• Prime time numbers on 6-digit clocks: numbers of the form HMMSS where H, MM, SS are primes, H < 24, MM and SS < 60.at n=22A295014
• The number of distinct positions on an infinite chessboard reachable by the (2,3)-leaper (or zebra) in at most n moves.at n=25A297740
• Irregular triangle read by rows: Numbers of unbranched k-5-catafusenes.at n=46A323944
• Irregular triangular array T; row n shows the coefficients of the (n-1)-st polynomial in the obverse convolution s(x)**t(x), where s(x) = x+1 and t(x) = F(n) = n-th Fibonacci number. See Comments.at n=50A375047