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A278029 a(1)=0; for n>1, a(n) = k if n is a non-prime-power, A007916(k), say; or 0 if n is a prime power. 6
0, 1, 2, 0, 3, 4, 5, 0, 0, 6, 7, 8, 9, 10, 11, 0, 12, 13, 14, 15, 16, 17, 18, 19, 0, 20, 0, 21, 22, 23, 24, 0, 25, 26, 27, 0, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 0, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 0, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 0 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

LINKS

Rémy Sigrist, Table of n, a(n) for n = 1..10000

N. J. A. Sloane, Maple programs for A007916, A278028, A278029, A052409, A089723, A277564

MATHEMATICA

FoldList[Boole[#2 != #1] #2 &, #] &@ Accumulate@ Array[Boole[And[# > 1, CoprimeQ @@ FactorInteger[#][[All, -1]]]] &, 81] (* Michael De Vlieger, Dec 18 2016 *)

CROSSREFS

Cf. A007916.

Sequence in context: A101336 A137218 A087819 * A066246 A198370 A173517

Adjacent sequences:  A278026 A278027 A278028 * A278030 A278031 A278032

KEYWORD

nonn

AUTHOR

N. J. A. Sloane, Nov 10 2016

STATUS

approved

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Last modified February 21 21:41 EST 2018. Contains 299427 sequences. (Running on oeis4.)