n-th 4k+1 prime times n-th 4k-1 prime.

Terms

a(0) =15a(1) =91a(2) =187a(3) =551a(4) =851a(5) =1271a(6) =2279a(7) =2867a(8) =4307a(9) =5963a(10) =6887a(11) =7979a(12) =9047a(13) =11639a(14) =14659a(15) =18923a(16) =20567a(17) =24047a(18) =27331a(19) =31459a(20) =32899a(21) =40991a(22) =44503a(23) =47959a(24) =54227a(25) =59987a(26) =62879a(27) =67159a(28) =73543a(29) =82319