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 A328459 Sorted positions of first appearances in A328458 (maximum run-length of nontrivial divisors) of each positive integer in the image. 1
 1, 2, 6, 12, 60, 420, 504, 840, 2520, 27720, 360360, 720720 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,2 LINKS EXAMPLE The sequence of terms > 1 together with their nontrivial divisors begins:     2: {}     6: {2,3}    12: {2,3,4,6}    60: {2,3,4,5,6,10,12,15,20,30}   420: {2,3,4,5,6,7,10,12,14,15,20,21,28,30,35,42,60,70,84,105,140,210}   504: {2,3,4,6,7,8,9,12,14,18,21,24,28,36,42,56,63,72,84,126,168,252} MATHEMATICA dav=Table[Switch[n, 1, 1, _, Max@@Length/@Split[DeleteCases[Divisors[n], 1|n], #2==#1+1&]], {n, 1000}]; Table[Position[dav, i][[1, 1]], {i, Union[dav]}]//Sort CROSSREFS Positions of first appearances in A328458. The version for all divisors is A051451. Cf. A000005, A033676, A060775, A070824, A119313, A129308, A181063, A199970, A163870, A328448, A328449. Sequence in context: A048803 A068625 A162935 * A051451 A090951 A168262 Adjacent sequences:  A328456 A328457 A328458 * A328460 A328461 A328462 KEYWORD nonn,more AUTHOR Gus Wiseman, Oct 17 2019 STATUS approved

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Last modified February 17 18:14 EST 2020. Contains 332005 sequences. (Running on oeis4.)