128257

Properties

Appears in sequences

• Octanacci numbers: a(0)=a(1)=...=a(6)=0, a(7)=1; for n >= 8, a(n) = Sum_{i=1..8} a(n-i).at n=25A079262
• a(n) is the number of n-tosses having a run of 6 or more heads for a fair coin (i.e., probability is a(n)/2^n).at n=20A143662
• Primes that belong to A156781, A156782 and A156783.at n=3A156785
• Primes in the union of all n-Fibonacci sequences.at n=22A227880
• Consider a number of k digits n = d_(k)*10^(k-1) + d_(k-1)*10^(k-2) + … + d_(2)*10 + d_(1). Sequence lists the numbers n such that Sum_{i=1..k-1}{sigma(Sum_{j=1..i}{d_(j)*10^(j-1)})} = Sum_{i=1..k-1}{phi(Sum_{j=1..i}{d_(k-j+1)*10^(i-j)})} (see example below).at n=18A244068
• Primes in the 8th-order Fibonacci numbers A079262.at n=2A253706
• Sequence defined by a(1)=a(2)=1 and a(n) = gray(gray(a(n-1)) + gray(a(n-2))), with gray(m) = A003188(m).at n=32A265386
• Primes equal to a centered pentagonal number plus 1.at n=37A285810
• Numbers that are both lucky-indexed primes and prime-indexed lucky numbers.at n=22A307009
• Number of non-alternating compositions of n, excluding twins (x,x).at n=18A348377
• Prime numbersat n=12007