Numbers k such that 1/(1/phi(k) + 1/phi(k+1) + 1/phi(k+2) + 1/phi(k+3)) is an integer.

Terms

a(0) =13a(1) =75a(2) =111a(3) =144a(4) =192a(5) =558a(6) =559a(7) =1683a(8) =2016a(9) =3624a(10) =7129a(11) =10369a(12) =11658a(13) =18362a(14) =19442a(15) =19800a(16) =19801a(17) =32772a(18) =47627a(19) =60482a(20) =82082a(21) =133988a(22) =143642a(23) =229321a(24) =291721a(25) =312483a(26) =352846a(27) =390603a(28) =395136a(29) =436801