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 A325761 Heinz numbers of integer partitions whose length is itself a part. 2
 1, 2, 6, 9, 15, 20, 21, 30, 33, 39, 45, 50, 51, 56, 57, 69, 70, 75, 84, 87, 93, 105, 110, 111, 123, 125, 126, 129, 130, 140, 141, 159, 165, 170, 175, 176, 177, 183, 189, 190, 195, 196, 201, 210, 213, 219, 230, 237, 245, 249, 255, 264, 267, 275, 285, 290, 291 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS The Heinz number of an integer partition (y_1,...,y_k) is prime(y_1)*...*prime(y_k). The enumeration of these partitions by sum is given by A002865. LINKS EXAMPLE The sequence of terms together with their prime indices begins:     1: {}     2: {1}     6: {1,2}     9: {2,2}    15: {2,3}    20: {1,1,3}    21: {2,4}    30: {1,2,3}    33: {2,5}    39: {2,6}    45: {2,2,3}    50: {1,3,3}    51: {2,7}    56: {1,1,1,4}    57: {2,8}    69: {2,9}    70: {1,3,4}    75: {2,3,3}    84: {1,1,2,4}    87: {2,10} MATHEMATICA Select[Range[100], MemberQ[PrimePi/@First/@FactorInteger[#], PrimeOmega[#]]&] CROSSREFS Cf. A001222, A002865, A056239, A093641, A109298, A110295, A112798, A118914, A325762, A325763. Sequence in context: A189760 A049634 A120387 * A176039 A260699 A084265 Adjacent sequences:  A325758 A325759 A325760 * A325762 A325763 A325764 KEYWORD nonn AUTHOR Gus Wiseman, May 18 2019 STATUS approved

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Last modified July 24 14:01 EDT 2021. Contains 346273 sequences. (Running on oeis4.)