

A363391


Numbers k such that k, k+1, k+2, k+3 have 2, 3, 4, 5 prime factors respectively, counted with multiplicity.


1



493, 2413, 3013, 3427, 3873, 4333, 4885, 5029, 5893, 6697, 7373, 8373, 10113, 10533, 13011, 14005, 14677, 15122, 16373, 17173, 17869, 18613, 19693, 20053, 20613, 22417, 23073, 23077, 23137, 23573, 24493, 24613, 24937, 25141, 26101, 26193, 26917, 27637, 27973, 28357, 29713, 29941, 31861, 32393
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OFFSET

1,1


COMMENTS

Numbers k such that A001222(k+j) = 2+j for j = 0,1,2,3.
The first k in the sequence such that A001222(k+4) = 6 is a(232) = 153221.
The first k in the sequence such that A001222(k+4) = 6 and A001222(k+5) = 7 is a(4716) = 2940571.


LINKS



EXAMPLE

a(3) = 3013 is a term because 3013 = 23 * 131 has 2 prime factors counted by multiplicity, 3014 = 2 * 11 * 137 has 3, 3015 = 3^2 * 5 * 67 has 4, and 3016 = 2^3 * 13 * 29 has 5.


MAPLE

R:= NULL: state:= 0: count:= 0:
for x from 1 while count < 50 do
v:= numtheory:bigomega(x);
if v = 2 then state:= 2
elif v = state+1 and state >= 2 then state:=state+1
else state:= 0
fi;
if state = 5 then count:= count+1; R:= R, x3;
fi;
od:
R;


CROSSREFS



KEYWORD

nonn


AUTHOR



STATUS

approved



