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 A325388 Heinz numbers of strict integer partitions with distinct differences (with the last part taken to be 0). 5
 1, 2, 3, 5, 7, 10, 11, 13, 14, 15, 17, 19, 22, 23, 26, 29, 31, 33, 34, 35, 37, 38, 39, 41, 43, 46, 47, 51, 53, 55, 57, 58, 59, 61, 62, 67, 69, 71, 73, 74, 77, 79, 82, 83, 85, 86, 87, 89, 91, 93, 94, 95, 97, 101, 103, 106, 107, 109, 111, 113, 115, 118, 119, 122 (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 differences of a sequence are defined as if the sequence were increasing, so for example the differences of (6,3,1) (with the last part taken to be 0) are (-3,-2,-1). The enumeration of these partitions by sum is given by A320348. LINKS EXAMPLE The sequence of terms together with their prime indices begins:     1: {}     2: {1}     3: {2}     5: {3}     7: {4}    10: {1,3}    11: {5}    13: {6}    14: {1,4}    15: {2,3}    17: {7}    19: {8}    22: {1,5}    23: {9}    26: {1,6}    29: {10}    31: {11}    33: {2,5}    34: {1,7}    35: {3,4} MATHEMATICA primeptn[n_]:=If[n==1, {}, Reverse[Flatten[Cases[FactorInteger[n], {p_, k_}:>Table[PrimePi[p], {k}]]]]]; Select[Range[100], SquareFreeQ[#]&&UnsameQ@@Differences[Append[primeptn[#], 0]]&] CROSSREFS A subsequence of A005117. Cf. A056239, A112798, A320348, A325324, A325327, A325362, A325364, A325366, A325367, A325368, A325390, A325405, A325460, A325461, A325467. Sequence in context: A087246 A090421 A109608 * A325405 A118241 A325160 Adjacent sequences:  A325385 A325386 A325387 * A325389 A325390 A325391 KEYWORD nonn AUTHOR Gus Wiseman, May 02 2019 STATUS approved

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Last modified January 28 06:29 EST 2020. Contains 331317 sequences. (Running on oeis4.)