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 A325170 Heinz numbers of integer partitions with origin-to-boundary graph-distance equal to 2. 10
 6, 9, 10, 12, 14, 15, 18, 20, 21, 22, 24, 25, 26, 27, 28, 33, 34, 35, 36, 38, 39, 40, 44, 46, 48, 49, 51, 52, 54, 55, 56, 57, 58, 62, 65, 68, 69, 72, 74, 76, 77, 80, 81, 82, 85, 86, 87, 88, 91, 92, 93, 94, 95, 96, 104, 106, 108, 111, 112, 115, 116, 118, 119 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS The origin-to-boundary graph-distance of a Young diagram is the minimum number of unit steps East or South from the upper-left square to a non-square in the lower-right quadrant. It is also the side-length of the minimum triangular partition contained inside the diagram. The Heinz number of an integer partition (y_1,...,y_k) is prime(y_1)*...*prime(y_k). LINKS Gus Wiseman, Young diagrams corresponding to the first 50 terms. EXAMPLE The sequence of terms together with their prime indices begins:    6: {1,2}    9: {2,2}   10: {1,3}   12: {1,1,2}   14: {1,4}   15: {2,3}   18: {1,2,2}   20: {1,1,3}   21: {2,4}   22: {1,5}   24: {1,1,1,2}   25: {3,3}   26: {1,6}   27: {2,2,2}   28: {1,1,4}   33: {2,5}   34: {1,7}   35: {3,4}   36: {1,1,2,2}   38: {1,8} MATHEMATICA primeMS[n_]:=If[n==1, {}, Flatten[Cases[FactorInteger[n], {p_, k_}:>Table[PrimePi[p], {k}]]]]; otb[ptn_]:=Min@@MapIndexed[#1+#2[[1]]-1&, Append[ptn, 0]]; Select[Range[200], otb[Reverse[primeMS[#]]]==2&] CROSSREFS Cf. A001221, A001222, A006918, A056239, A065770, A112798, A174090, A257990, A297113, A325167, A325169. Sequence in context: A091886 A333357 A111774 * A325229 A036347 A129492 Adjacent sequences:  A325167 A325168 A325169 * A325171 A325172 A325173 KEYWORD nonn AUTHOR Gus Wiseman, Apr 05 2019 STATUS approved

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Last modified November 27 14:10 EST 2020. Contains 338683 sequences. (Running on oeis4.)