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A138962 a(1)=1; a(n+1) = the smallest prime divisor of A138793(n+1). 6
1, 3, 3, 29, 3, 3, 19, 3, 3, 457, 3, 3, 16087, 3, 3, 35963, 3, 3, 167, 3, 3, 7, 3, 3, 13, 3, 3, 953, 3, 3, 7, 3, 3, 548636579, 3, 3, 19, 3, 3, 71, 3, 3, 13, 3, 3, 89, 3, 3, 114689, 3, 3, 17, 3, 3, 12037, 3, 3, 7, 3, 3 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

a(61) > 10^11. - Robert Price, Mar 22 2015

LINKS

Table of n, a(n) for n=1..60.

MATHEMATICA

b = {}; a = {}; Do[w = RealDigits[n]; w = First[w]; Do[AppendTo[a, w[[k]]], {k, 1, Length[w]}]; p = FromDigits[Reverse[a]]; AppendTo[b, First[First[FactorInteger[p]]]], {n, 1, 31}]; b (* Artur Jasinski, Apr 04 2008 *)

lst = {}; Table[First[First[FactorInteger[FromDigits[Reverse[lst = Join[lst, IntegerDigits[n]]]]]]], {n, 1, 60}] (* Robert Price, Mar 22 2015 *)

CROSSREFS

Cf. A104759, A000422, A116504, A007908, A116505, A104759, A075019, A075020, A075021, A075022, A138789, A138790, A138958, A138959, A138960, A138962.

Sequence in context: A098340 A271938 A075020 * A139206 A100651 A124244

Adjacent sequences:  A138959 A138960 A138961 * A138963 A138964 A138965

KEYWORD

nonn

AUTHOR

Artur Jasinski, Apr 04 2008

EXTENSIONS

a(32)-a(60) from Robert Price, Mar 22 2015

STATUS

approved

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Last modified July 21 02:02 EDT 2019. Contains 325189 sequences. (Running on oeis4.)