Numbers k such that sopf(k) = sopf(k+3), where sopf(k) = A008472(k).

Terms

a(0) =7a(1) =60a(2) =147a(3) =407a(4) =470a(5) =1053a(6) =1175a(7) =3431a(8) =3822a(9) =5126a(10) =5960a(11) =6280a(12) =6321a(13) =6897a(14) =7200a(15) =8687a(16) =9243a(17) =10760a(18) =12614a(19) =15093a(20) =16153a(21) =18080a(22) =18818a(23) =19668a(24) =20433a(25) =20976a(26) =24648a(27) =26826a(28) =30804a(29) =44016