69876

Appears in sequences

• Values of n such that N=(an+1)(bn+1)(cn+1) is a 3-Carmichael number (A087788), where a,b,c = 1,2,33.at n=18A064253
• Numbers m such that N = (am+1)(bm+1)(cm+1) is a 3-Carmichael number (A087788), where a,b,c = 1,2,55.at n=10A065696
• Pentagonal numbers not divisible by 10 whose reverse is triangular.at n=5A066757
• Riordan array (1/(1-2x), x(1-x)/(1-2x)^2).at n=59A114164
• Pentagonal numbers > 0 which are not the difference of two other pentagonal numbers > 0.at n=17A135769
• Pentagonal numbers > 0 which are not the difference of two larger pentagonal numbers.at n=24A136113
• Number of lower triangular n X n arrays colored with integers 0 upwards introduced in row major order, with no element equal to any horizontal, vertical, diagonal or antidiagonal neighbor, and containing the value n(n+1)/2-2.at n=26A211911
• Pentagonal numbers (A000326) in which parity of digits alternates.at n=26A297644