



425, 845, 1265, 1643, 1925, 2525, 2873, 3335, 3395, 3575, 3683, 3971, 4163, 4307, 4343, 4475, 4613, 4667, 4805, 5141, 5285, 5423, 5603, 5945, 6095, 6305, 6683, 6851, 6875, 6893, 6923, 7337, 7661, 7733, 7973, 8075, 8303, 8393, 8453, 8723, 8825, 9191, 9425, 9581, 9821, 9875
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OFFSET

1,1


COMMENTS

Numbers k such that both k and k+2 are in A349939.
Numbers k == 5 (mod 6) such that, the smallest number with exactly k divisors is smaller than the smallest number with exactly k1 or k+1 divisors, and that the smallest number with exactly k+2 divisors is smaller than the smallest number with exactly k+1 or k+3 divisors.


LINKS



EXAMPLE

The smallest numbers with exactly 424, 425, 426, 427 and 428 divisors are 472877960873902080, 3317760000, 53126622932283508654080, 840479776858391445504 and 1216944576219100225436835077160960 respectively. The smallest number with exactly 425 divisors is smaller than the smallest number with exactly 424 or 426 divisors, the smallest number with exactly 427 divisors is smaller than the smallest number with exactly 426 or 428 divisors, and 425 == 5 (mod 6), so 425 is a term.


PROG

(PARI) isA349940(k) = if(k%6==5, my(v=vector(5, n, A005179(k2+n))); v[2]<v[1] && v[2]<v[3] && v[4]<v[3] && v[4]<v[5], 0) \\ See A005179 for its program


CROSSREFS



KEYWORD

nonn


AUTHOR



STATUS

approved



