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 A302797 Squarefree numbers whose prime indices are pairwise coprime. Heinz numbers of strict integer partitions with pairwise coprime parts. 13
 1, 2, 6, 10, 14, 15, 22, 26, 30, 33, 34, 35, 38, 46, 51, 55, 58, 62, 66, 69, 70, 74, 77, 82, 85, 86, 93, 94, 95, 102, 106, 110, 118, 119, 122, 123, 134, 138, 141, 142, 143, 145, 146, 154, 155, 158, 161, 165, 166, 170, 177, 178, 186, 187, 190, 194, 201, 202 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS A prime index of n is a number m such that prime(m) divides n. Two or more numbers are coprime if no pair of them has a common divisor other than 1. A single number is not considered coprime unless it is equal to 1. The Heinz number of an integer partition (y_1,...,y_k) is prime(y_1)*...*prime(y_k). LINKS EXAMPLE Sequence of terms together with their sets of prime indices begins: 01 : {} 02 : {1} 06 : {1,2} 10 : {1,3} 14 : {1,4} 15 : {2,3} 22 : {1,5} 26 : {1,6} 30 : {1,2,3} 33 : {2,5} 34 : {1,7} 35 : {3,4} 38 : {1,8} 46 : {1,9} 51 : {2,7} 55 : {3,5} 58 : {1,10} 62 : {1,11} 66 : {1,2,5} 69 : {2,9} 70 : {1,3,4} MATHEMATICA Select[Range[100], Or[#===1, SquareFreeQ[#]&&CoprimeQ@@PrimePi/@FactorInteger[#][[All, 1]]]&] CROSSREFS Cf. A001222, A003963, A005117, A007359, A051424, A056239, A275024, A289509, A302242, A302505, A302696, A302697, A302698, A302796, A302798. Sequence in context: A080324 A165562 A302796 * A130319 A191256 A067368 Adjacent sequences:  A302794 A302795 A302796 * A302798 A302799 A302800 KEYWORD nonn AUTHOR Gus Wiseman, Apr 13 2018 STATUS approved

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Last modified January 28 03:28 EST 2020. Contains 331314 sequences. (Running on oeis4.)