

A326232


Numbers k such that N = k^2 is a twin rank (cf. A002822: 6N + 1 are twin primes).


8



1, 5, 10, 35, 60, 70, 75, 210, 240, 385, 430, 445, 495, 590, 655, 730, 805, 815, 835, 1005, 1040, 1045, 1230, 1390, 1430, 1530, 1670, 1715, 1850, 1890, 1920, 2000, 2020, 2100, 2110, 2245, 2310, 2405, 2415, 2495, 2545, 2685, 2755, 2840, 2935, 2950, 3045, 3255, 3260, 3335, 3420, 3650, 3775, 3805
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OFFSET

1,2


COMMENTS

Dinculescu notes that when k^2 > 1 is a twin rank (i.e., in A002822), then k is always a multiple of 5, and if k^3 > 1 is a twin rank, it is divisible by 7. See A326231 for the terms > 1 divided by 5.


LINKS



PROG

(PARI) select( is(n)=!for(s=1, 2, ispseudoprime(6*n^2+(1)^s)return), [1..5000])


CROSSREFS



KEYWORD

nonn


AUTHOR



STATUS

approved



