2097024

Appears in sequences

• a(n) is the number of distinct patterns (modulo geometric D3-operations) with strict median-reflective (palindrome) symmetry (i.e., having no other symmetry) which can be formed by an equilateral triangular arrangement of closely packed black and white cells satisfying the local matching rule of Pascal's triangle modulo 2, where n is the number of cells in each edge of the arrangement. The matching rule is such that any elementary top-down triangle of three neighboring cells in the arrangement contains either one or three white cells.at n=40A060549
• a(n) is the number of distinct patterns (modulo geometric D3-operations) with strict median-reflective (palindrome) symmetry (i.e., having no other symmetry) which can be formed by an equilateral triangular arrangement of closely packed black and white cells satisfying the local matching rule of Pascal's triangle modulo 2, where n is the number of cells in each edge of the arrangement. The matching rule is such that any elementary top-down triangle of three neighboring cells in the arrangement contains either one or three white cells.at n=41A060549
• a(n) = (4*n-1)*4*n*(4*n+1).at n=32A069140
• List of codewords in binary lexicode with Hamming distance 14 written as decimal numbers.at n=3A075958
• Difference of two positive 7th powers.at n=27A181126
• Array: row n shows the coefficients of the characteristic polynomial of the n-th principal submatrix of f(i,j)=(2i-1 if i=j and 1 otherwise) for i>=1 and j>=1 (as in A204131).at n=37A204132
• Primitive non-solvable numbers: orders of non-solvable groups such that all groups with order a proper divisor of that order are solvable.at n=24A216480
• a(n) = 8^n - 2^n.at n=7A248217
• Primitive non-solvable numbers: elements of A056866 not divisible by any earlier term.at n=19A257146
• T(n, k) = [x^n] 2^n*P(n, x), where P(n, x) = (1 + 4*x)^(n + 1) + (1 - 2^(-2*n-1))*(2 + 4*x)^(n + 1). Triangle read by rows, T(n, k) for 0 <= k <= n+1 if n >= 0 and by convention T(-1, 0) = 0.at n=35A342317
• Orders of simple groups PSL(2,K) with exactly 4 prime divisors.at n=18A364004
• Numbers k such that k is a multiple of A163511(k).at n=28A364496
• Area of the unique primitive Pythagorean triple whose inradius is the n-th odd prime and whose short leg is an even number.at n=29A380302