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 A324522 Numbers > 1 where the minimum prime index is equal to the number of prime factors counted with multiplicity. 24
 2, 9, 15, 21, 33, 39, 51, 57, 69, 87, 93, 111, 123, 125, 129, 141, 159, 175, 177, 183, 201, 213, 219, 237, 245, 249, 267, 275, 291, 303, 309, 321, 325, 327, 339, 381, 385, 393, 411, 417, 425, 447, 453, 455, 471, 475, 489, 501, 519, 537, 543, 573, 575, 579, 591 (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 integer partitions where the minimum part is equal to the number of parts (A006141). The Heinz number of an integer partition (y_1, ..., y_k) is prime(y_1) * ... * prime(y_k). LINKS Alois P. Heinz, Table of n, a(n) for n = 1..10000 FORMULA A055396(a(n)) = A001222(a(n)). EXAMPLE The sequence of terms together with their prime indices begins:     2: {1}     9: {2,2}    15: {2,3}    21: {2,4}    33: {2,5}    39: {2,6}    51: {2,7}    57: {2,8}    69: {2,9}    87: {2,10}    93: {2,11}   111: {2,12}   123: {2,13}   125: {3,3,3}   129: {2,14}   141: {2,15}   159: {2,16}   175: {3,3,4} MAPLE with(numtheory): q:= n-> is(pi(min(factorset(n)))=bigomega(n)): select(q, [\$2..600])[];  # Alois P. Heinz, Mar 07 2019 MATHEMATICA Select[Range[2, 100], PrimePi[FactorInteger[#][[1, 1]]]==PrimeOmega[#]&] CROSSREFS Cf. A001222, A006141, A055396, A056239, A106529, A112798, A256617. Cf. A324515, A324517, A324519, A324521, A324522, A324560, A324562. Sequence in context: A184531 A063105 A215035 * A319967 A063094 A108463 Adjacent sequences:  A324519 A324520 A324521 * A324523 A324524 A324525 KEYWORD nonn AUTHOR Gus Wiseman, Mar 06 2019 STATUS approved

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Last modified August 2 21:30 EDT 2021. Contains 346429 sequences. (Running on oeis4.)