71500

Appears in sequences

• Expansion of 1/((1-x)*(1-x^2))^4.at n=19A038164
• G.f.: 1/((1-x)*(1-x^2))^5.at n=14A038165
• Expansion of (-1 + 1/(1-10*x)^10)/(100*x); related to A053109.at n=3A053113
• Expansion of (1+10*x+5*x^2)/(1-x)^10.at n=7A059601
• a(n) = C(n+3,3)*n^3/4.at n=10A085284
• a(1) = 1. For n > 1, a(n) = a(n-1) if n is prime, a(n) = a(n-1)/n if n is composite and divides a(n-1) else a(n) = n*a(n-1).at n=26A088304
• a(n) = sigma_3(n) - sigma_2(n).at n=39A092349
• Number of permutations of [n] with exactly 2 descents which avoid the pattern 1324.at n=14A098992
• a(n) is the number of nonnegative integers k less than 10^n such that the decimal representation of k lacks at least one of digits 1,2, at least one of digits 3,4 and at least one of digits 5,6,7,8,9.at n=4A125945
• Ratio of quadruple Sum of k^2-1 to quadruple sum of k made into an integer sequence: (1/6)*(-1 + n)*(2 + n)*(3 + n)*(7 + n).at n=22A130863
• Number of (n+2) X 5 binary arrays avoiding patterns 001 and 101 in rows and columns.at n=7A202197
• Numbers with the property that in their factorization over distinct terms of A050376, the sums of prime and nonprime terms of A050376 are equal.at n=36A241270
• a(n) = n*(n+1)*(7*n+2)/6.at n=39A255211
• Number of multisets of exactly three partitions of positive integers into distinct parts with total sum of parts equal to n.at n=29A320788
• Positive integers which can be written in two bases smaller than 10 as mutually-reversed strings of digit(s).at n=29A336733
• Irregular triangle where the n-th row list the positive integers which can be written in two bases smaller than n as mutually-reversed strings of digit(s), for n>=4.at n=56A336768