Numbers k such that in a rotated-square spiral with positive integers (A215468) among k's eight nearest neighbors five or more are primes.

A215471

Numbers k such that in a rotated-square spiral with positive integers (A215468) among k's eight nearest neighbors five or more are primes.

Terms

    a(0) =8a(1) =30a(2) =138a(3) =658a(4) =2620a(5) =3010a(6) =3168a(7) =3372a(8) =3462a(9) =8628a(10) =11940a(11) =17682a(12) =24918a(13) =27918a(14) =32560a(15) =39228a(16) =39790a(17) =40128a(18) =43608a(19) =48532a(20) =53268a(21) =55372a(22) =56040a(23) =56712a(24) =73362a(25) =85200a(26) =85888a(27) =90646a(28) =96052a(29) =101748

External references