A078151 Smallest k such that d(phi(k)) - phi(d(k)) = -n, where d(k) = A000005(k) and phi(k) = A000010(k).
240, 120, 960, 6528, 4080, 1920, 15360, 24960, 61440, 13440, 16320, 87360, 983040, 196560, 1432080, 130560, 861840, 32640, 98280, 114240, 2545920, 293760, 261120, 967680, 174720, 2673216, 4194240, 1081080, 1044480, 913920, 1659840, 424320
Offset: 1
Examples
a(77)=2970240, since d(phi(2970240)) - phi(d(2970240)) = -77 first appears here; while d(phi(x)) - phi(d(x)) takes large positive values,absolute value of negative differences grows significantly slower.