26979

Appears in sequences

• Number of alternating compositions, i.e., compositions with alternating increases and decreases, starting with either an increase or a decrease.at n=23A025047
• Integers k such that nextprime(k^5) - prevprime(k^5) = 4.at n=24A090123
• Indices of primes in sequence defined by A(0) = 49, A(n) = 10*A(n-1) - 31 for n > 0.at n=13A101728
• Let prime(0) = 1 and f(n) = product prime(d), where d ranges over all the decimal digits of n. The sequence gives numbers n such that f(n) == 0 (mod n).at n=5A113735
• Number of n X n binary arrays symmetric under 90 degree rotation with all ones connected only in a 1000-1111-0010-0010 pattern in any orientation.at n=15A147176
• a(n) = n^2*(2*n + 5).at n=23A163683
• Integers of the form A164577(k)/3.at n=32A164619
• a(n) = 16*n^2 + 2*n + 1.at n=41A204675
• Poincaré series for invariant polynomial functions on the space of binary forms of degree 9.at n=26A293934
• Number of alternating compositions of n, including twins (x,x).at n=23A344604