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A070232
a(1) = 4; a(n) = smallest composite number greater than the sum of all previous terms.
1
4, 6, 12, 24, 48, 95, 190, 380, 760, 1520, 3040, 6080, 12160, 24320, 48640, 97280, 194560, 389120, 778240, 1556480, 3112960, 6225920, 12451840, 24903680, 49807360, 99614720, 199229440, 398458880, 796917760, 1593835520, 3187671040
OFFSET
1,1
COMMENTS
a(n) = 95*2^(n-6) for n > 5.
LINKS
MATHEMATICA
a = {4}; Do[b = 1 + Plus @@ a; While[ PrimeQ[b], b++ ]; a = Append[a, b], {n, 2, 30}]; a
nxt[{t_, a_}]:=Module[{k=t+1}, While[!CompositeQ[k], k++]; {t+k, k}]; NestList[nxt, {4, 4}, 30][[;; , 2]] (* Harvey P. Dale, Sep 14 2024 *)
CROSSREFS
Cf. A070218.
Sequence in context: A162688 A362883 A352634 * A037100 A095969 A090608
KEYWORD
nonn
AUTHOR
Amarnath Murthy, May 05 2002
EXTENSIONS
Edited by Robert G. Wilson v, May 06 2002
STATUS
approved