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Indices of records in A100949.
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%I #11 Jun 14 2024 12:37:17

%S 6,9,11,17,38,51,62,88,93,98,122,148,152,188,222,232,248,266,272,296,

%T 308,326,388,398,458,488,500,518,572,602,686,692,708,860,912,972,992,

%U 1068,1112,1128,1146,1152,1270,1272,1340,1356,1422,1536,1542,1578

%N Indices of records in A100949.

%F Numbers n such that the number of partitions of n into a prime and a semiprime is a record.

%e a(15) = 222 because there are 22 partitions of n into a prime and a semiprime and that 22 is a record.

%e For n = 6, 9, 11, 17, 38, 51, 62, 88, 93, 98, 122, 148, 152, 188, 222, A100949(n) = 1, 2, 3, 5, 6, 8, 10, 11, 12, 13, 16, 17, 19, 21, 22.

%t nPar[n_] := Length@ Select[Prime@ Range[ PrimePi@ n], PrimeOmega[n - #] == 2 &]; r = 0; L = {}; n = 2; While[Length[L] < 50, p = nPar[++n]; If[p > r, r = p; AppendTo[L, n]]]; L (* _Giovanni Resta_, Jun 19 2016 *)

%t DeleteDuplicates[Table[{n,Count[Sort/@(PrimeOmega/@IntegerPartitions[n,{2}]),{1,2}]},{n,1600}],GreaterEqual[#1[[2]],#2[[2]]]&][[;;,1]]//Rest (* _Harvey P. Dale_, Jun 14 2024 *)

%Y Cf. A000040, A001358, A061358, A100949.

%K nonn

%O 1,1

%A _Jonathan Vos Post_, Oct 04 2007

%E Data corrected by _Giovanni Resta_, Jun 19 2016