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A071247 Numbers n such that A078142(n) = A078142(n+1), where A078142(n) is the sum of the differences of the distinct prime factors p of n and the next square larger than p. 2
7, 12, 19, 29, 86, 96, 99, 121, 132, 138, 153, 154, 164, 183, 192, 220, 230, 234, 251, 274, 280, 286, 353, 390, 444, 455, 476, 484, 539, 589, 651, 675, 704, 730, 774, 785, 813, 850, 867, 944, 965, 1069, 1152, 1216, 1238, 1250, 1266, 1280, 1299, 1308, 1333 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Amiram Eldar, Table of n, a(n) for n = 1..10000

MATHEMATICA

s[n_] := Total[Ceiling[Sqrt[(p = FactorInteger[n][[;; , 1]])]]^2 - p]; s0 = 0; seq = {}; Do[s2 = s[n]; If[s1 == s2, AppendTo[seq, n - 1]]; s1 = s2, {n, 2, 1334}]; seq (* Amiram Eldar, Dec 05 2019 *)

CROSSREFS

Cf. A078142.

Sequence in context: A190495 A271988 A093330 * A025006 A189321 A273072

Adjacent sequences:  A071244 A071245 A071246 * A071248 A071249 A071250

KEYWORD

nonn

AUTHOR

Jason Earls, Nov 20 2002

STATUS

approved

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Last modified August 15 12:09 EDT 2022. Contains 356145 sequences. (Running on oeis4.)