77575

Appears in sequences

• a(n) = Sum_{k=0,1,2,...,n-4,n-2,n-1} a(k); a(n-3) is not a summand, with a(0)=0, a(1)=1, a(2)=3.at n=19A049859
• Numbers whose digits are prime and which retain this property when multiplied by some 1-digit prime (i.e., one of 2, 3, 5 or 7).at n=30A227922
• a(n) = n*(n + 1)*(19*n - 16)/6.at n=29A237618