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 A324517 Numbers > 1 where the maximum prime index equals the number of prime factors minus the number of distinct prime factors. 11
 4, 24, 27, 36, 54, 80, 200, 224, 240, 360, 405, 500, 540, 600, 625, 672, 675, 704, 784, 810, 900, 1008, 1120, 1125, 1250, 1350, 1500, 1512, 1664, 1701, 1875, 2112, 2250, 2268, 2352, 2744, 2800, 3168, 3360, 3402, 3520, 3528, 3750, 3872, 3920, 3969, 4352, 4752 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS A prime index of n is a number m such that prime(m) divides n. The multiset of prime indices of n is row n of A112798. Also Heinz numbers of the integer partitions enumerated by A324518. The Heinz number of an integer partition (y_1, ..., y_k) is prime(y_1) * ... * prime(y_k). LINKS FORMULA A061395(a(n)) = A001222(a(n)) - A001221(a(n)) = A046660(a(n)). EXAMPLE The sequence of terms together with their prime indices begins:     4: {1,1}    24: {1,1,1,2}    27: {2,2,2}    36: {1,1,2,2}    54: {1,2,2,2}    80: {1,1,1,1,3}   200: {1,1,1,3,3}   224: {1,1,1,1,1,4}   240: {1,1,1,1,2,3}   360: {1,1,1,2,2,3}   405: {2,2,2,2,3}   500: {1,1,3,3,3}   540: {1,1,2,2,2,3}   600: {1,1,1,2,3,3}   625: {3,3,3,3}   672: {1,1,1,1,1,2,4}   675: {2,2,2,3,3}   704: {1,1,1,1,1,1,5}   784: {1,1,1,1,4,4}   810: {1,2,2,2,2,3}   900: {1,1,2,2,3,3} MATHEMATICA Select[Range[2, 1000], With[{f=FactorInteger[#]}, PrimePi[f[[-1, 1]]]==Total[Last/@f]-Length[f]]&] CROSSREFS Cf. A001221, A001222, A046660, A056239, A061395, A112798, A243055, A256617. Cf. A324515, A324518, A324519, A324521, A324522, A324560, A324562. Sequence in context: A222595 A103225 A303333 * A137980 A144137 A238222 Adjacent sequences:  A324514 A324515 A324516 * A324518 A324519 A324520 KEYWORD nonn AUTHOR Gus Wiseman, Mar 06 2019 STATUS approved

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Last modified April 21 15:55 EDT 2021. Contains 343156 sequences. (Running on oeis4.)