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A268314
First term of a run of at least 11 consecutive integers which are not squarefree.
6
221167422, 1407472722, 3639720042, 3865964268, 4982931368, 5005996146, 7108776620, 8044261244, 10249558974, 12766690268, 13585489166, 19792784322, 26995377572, 30410811296, 30477326444, 32070270968, 34317891368, 39956560824, 40841363528, 42216508746, 43133805944, 46295514872, 47255689915
OFFSET
1,1
COMMENTS
a(23) is the first term beginning a 12-chain. - Bill Hannaford, Oct 06 2016
FORMULA
A268314 = { A268313[k] | A268313[k+1] = A268313[k]+1 } = { A078143[k] | A078143[k+2] = A078143[k]+2 } = { A077647[k] | A077647[k+3] = A077647[k]+3 } = { A077640[k] | A077640[k+4] = A077640[k]+4 }.
MATHEMATICA
s11[x_] := Apply[Plus, Table[Abs[MoebiusMu[x+j]], {j, 0, 10}]]; Do[If[Equal[s11[n], 0], Print[n]], {n, 10^8, 10^13}]
CROSSREFS
Cf. A013929, A045882 (first of the k-chains), A051681.
Cf. A068781 (2-chains), A070258 (3-chains), A070284 (4-chains), A078144 (5-chains), A049535 (6-chains), A077640 (7-chains), A077647 (8-chains), A078143 (9-chains), A268313 (10-chains).
Sequence in context: A250599 A114672 A268313 * A231630 A231092 A228965
KEYWORD
nonn
AUTHOR
M. F. Hasler, Feb 01 2016
EXTENSIONS
a(12)-a(23) from Bill Hannaford, Oct 06 2016
STATUS
approved