23431

Properties

Appears in sequences

• Primes p such that p+1 is palindromic.at n=37A028981
• Number of partitions of n with equal nonzero number of parts congruent to each of 1 and 3 (mod 4).at n=48A035550
• A035550 with periodic zeros stripped.at n=23A035595
• Triangle read by rows giving number of arrangements of k dumbbells on 2 X n grid (n >= 0, k >= 0).at n=61A046741
• Arrays of dumbbells.at n=6A055608
• Seventh column of A046741.at n=4A062127
• Number of ways of pairing odd numbers in the range 1 to n with even numbers in the range n+1 to 2n such that each pair sums to a prime.at n=20A071058
• Smallest prime with "n^3" as central digit(s).at n=7A084430
• Primes whose decimal representation is a valid number in base 5 and interpreted as such is again a prime.at n=39A090708
• Primes that are a concatenation of 2, 3 and a prime.at n=16A101218
• Primes and their indices such that when their respective SOD's are both prime, the SOD of the index is the nextprime of the prime SOD.at n=37A117458
• Numbers of the form prime(prime(prime(k))) with a digit sum which is prime.at n=36A162252
• a(n) = n^5 + 5*n + 5^n.at n=6A220511
• Primes formed from concatenation of PrimePi(n) and prime(n).at n=29A236551
• Indices of primes in the tribonacci-like sequence A214827.at n=31A242324
• Primes p such that p^3-2 and p^2-2 are both primes.at n=28A242979
• Decimal representation of the x-axis, from the left edge to the origin, of the n-th stage of growth of the two-dimensional cellular automaton defined by "Rule 595", based on the 5-celled von Neumann neighborhood.at n=16A283212
• Triangle T(n,k) read by rows, giving even-numbered coefficients of the matching polynomial of the n-ladder graph.at n=59A308244
• Primes p such that 2*p+q and 2*p+r are prime, where q and r are the next two primes after p.at n=38A340225
• Number of compositions of n into exactly n nonnegative parts such that each positive i-th part has the same parity as i.at n=12A348478