

A176650


Numbers k such that nonnegative nonsemiprime(k)+3 = nonnegative nonsemiprime(k+3).


1



1, 11, 12, 18, 19, 20, 26, 27, 28, 47, 53, 63, 64, 65, 66, 67, 68, 69, 73, 83, 84, 91, 92, 93, 98, 99, 100, 101, 102, 109, 115, 116, 117, 118, 122, 128, 129, 130, 134, 135, 136, 148, 152, 153, 154, 155, 156, 161, 162, 163, 164, 165, 166, 174, 183, 184, 185, 192, 193
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OFFSET

1,2


COMMENTS

Where nonnegative nonsemiprime numbers are zero together with A100959 (i.e., 0, 1, 2, 3, 5, 7, 8, 11, 12, 13, 16, 17, 18, 19, 20, 23, 24, 27, 28, 29, 30, ...).


LINKS

Jinyuan Wang, Table of n, a(n) for n = 1..10000


EXAMPLE

1 is a term because nonnegative nonsemiprime(1)+3 = 3 = nonnegative nonsemiprime(1+3).


MAPLE

A100959 := proc(n) option remember; if n = 1 then 1; else for a from procname(n1)+1 do if numtheory[bigomega](a) <> 2 then return a; end if; end do end if; end proc:
nnnspr := proc(n) if n = 1 then 0; else A100959(n1) ; end if; end proc:
isA176650 := proc(n) nnnspr(n) + 3 = nnnspr(n+3) ; end proc:
for n from 1 to 1200 do if isA176650(n) then printf("%d, ", n) ; end if; end do:
# R. J. Mathar, Apr 26 2010


CROSSREFS

Cf. A100959 (nonsemiprimes).
Sequence in context: A079350 A070605 A087450 * A046465 A134926 A105744
Adjacent sequences: A176647 A176648 A176649 * A176651 A176652 A176653


KEYWORD

nonn


AUTHOR

JuriStepan Gerasimov, Apr 22 2010


EXTENSIONS

Entries checked by R. J. Mathar, Apr 26 2010


STATUS

approved



