30247

Appears in sequences

• Numbers k such that k and k+1 have the same sum of unitary divisors (A034448).at n=35A064125
• The square root of A134779.at n=19A134780
• Triangle T(n, k) = binomial(n, k) + binomial(k*(n-k), n) + 2*(-1)^n*StirlingS1(n, k)*StirlingS1(n, n-k), read by rows.at n=29A155826
• Triangle T(n, k) = binomial(n, k) + binomial(k*(n-k), n) + 2*(-1)^n*StirlingS1(n, k)*StirlingS1(n, n-k), read by rows.at n=34A155826
• a(n) = 36*n^2 - n.at n=28A157286
• a(n) = 841*n^2 - 29.at n=5A158667
• Row 4 of table A162430.at n=28A162433
• Sums of 4 distinct primorials.at n=20A177709
• T(i, j) = k is the least squarefree number with a run of exactly i>=0 nonsquarefree numbers immediately preceding k and a run of exactly j>=0 nonsquarefree numbers immediately succeeding k.at n=26A270996
• Number of nX6 0..1 arrays with every element equal to 0, 1, 4, 5 or 6 horizontally, diagonally or antidiagonally adjacent elements, with upper left element zero.at n=8A303312
• Numbers obtained by reinterpreting base-2 representation of odd numbers in primorial base.at n=42A328462
• Numbers that are palindromes in primorial base.at n=46A333423
• Starts of runs of 4 consecutive Gray-code Niven numbers (A344341).at n=29A344344
• Numbers k such that k and k+1 have the same average of unitary divisors.at n=24A349222
• Numbers k such that A003415(k) >= A276086(k) and gcd(k, A003415(k)) = gcd(k, A276086(k)), where A003415 is the arithmetic derivative, and A276086 is the primorial base exp-function.at n=35A369959