404550

Appears in sequences

• Numbers k such that phi(k) is equal to A008473(k).at n=29A039779
• 1 / min{1/n - 1/a - 1/b > 0}, where a and b are integers.at n=28A045470
• Numbers k such that phi(k) = Sum_{d|k} core(d) where core(x) is the squarefree part of x (A007913).at n=28A074786
• a(n) = n^2 * (n^2 - 1)/2.at n=29A083374
• Triangular numbers composed of digits {0,4,5}.at n=4A119071
• Row sums of the triangle A045975.at n=29A204558
• Integral factorial ratio sequence: a(n) = (8*n)!*(3*n)!/((6*n)!*(4*n)!*n!).at n=4A211421
• The smaller of two consecutive triangular numbers which are permutations of each other.at n=0A247305
• Triangular numbers that are the product of a triangular number and an oblong number.at n=39A253652
• Triangular numbers n such that each decimal digit of n is equal to the difference of at least two other digits of n.at n=25A255917