Smallest even k such that lpf(k-1) = prime(n), while lpf(k-3) > prime(n), where lpf=least prime factor (A020639).

A242489

Smallest even k such that lpf(k-1) = prime(n), while lpf(k-3) > prime(n), where lpf=least prime factor (A020639).

Terms

    a(0) =10a(1) =26a(2) =50a(3) =254a(4) =170a(5) =392a(6) =362a(7) =944a(8) =842a(9) =1892a(10) =1370a(11) =2420a(12) =1850a(13) =2210a(14) =3764a(15) =6314a(16) =3722a(17) =4892a(18) =5042a(19) =7082a(20) =8612a(21) =9380a(22) =7922a(23) =12320a(24) =11414a(25) =10610a(26) =11450a(27) =13844a(28) =18872a(29) =16130

External references