27631

Properties

Appears in sequences

• a(n) = 12*a(n-1) - 31*a(n-2) for n > 1; a(0) = 1, a(1) = 7.at n=5A163306
• Number A(n,k) of 3n-length k-ary words, either empty or beginning with the first letter of the alphabet, that can be built by repeatedly inserting triples of identical letters into the initially empty word; square array A(n,k), n>=0, k>=0, by antidiagonals.at n=50A213027
• Number of 3n-length 4-ary words, either empty or beginning with the first letter of the alphabet, that can be built by repeatedly inserting triples of identical letters into the initially empty word.at n=5A218474
• Smaller of the two consecutive primes whose sum is a triangular number.at n=33A225077
• Primes p such that p^4 - p +/- 1 are twin primes.at n=18A236952
• Odd numbers n such that the sum of the binary digits of n and n^2 both equal 12.at n=30A261593
• Number of compositions (ordered partitions) of n into distinct parts such that number of parts is odd.at n=31A332304
• G.f. A(x) satisfies A(x) = 1 / ((1 + x) * (1 - 2 * x * A(x)^2)).at n=6A349255
• Prime numbersat n=3015