

A062091


a(1) = 2, a(n)= smallest even number which does not divide the product of all previous terms.


3



2, 4, 6, 10, 14, 18, 22, 26, 34, 38, 46, 50, 58, 62, 74, 82, 86, 94, 98, 106, 118, 122, 134, 142, 146, 158, 162, 166, 178, 194, 202, 206, 214, 218, 226, 242, 254, 262, 274, 278, 298, 302, 314, 326, 334, 338, 346, 358, 362, 382, 386, 394, 398, 422, 446, 454
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OFFSET

1,1


LINKS



FORMULA

2 and 4 together with numbers of the form 2*{p^(2^k)} where p is an odd prime and k is a nonnegative integer. [Corrected by Peter Munn, Nov 03 2020]


EXAMPLE

After 10 the next term in the sequence is 14 (not 12) as 12 = 2*6 divides the product of all the previous terms.


MATHEMATICA

Block[{a = {2}, k = 4, P = 1}, Do[Set[P, P*a[[1]]]; While[Mod[P, k] == 0, k += 2]; AppendTo[a, k], {i, 2, 56}]; a] (* Michael De Vlieger, Nov 04 2020 *)


CROSSREFS



KEYWORD

nonn


AUTHOR



EXTENSIONS



STATUS

approved



