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A131834 Indices of records in A100949. 0
6, 9, 11, 17, 38, 51, 62, 88, 93, 98, 122, 148, 152, 188, 222, 232, 248, 266, 272, 296, 308, 326, 388, 398, 458, 488, 500, 518, 572, 602, 686, 692, 708, 860, 912, 972, 992, 1068, 1112, 1128, 1146, 1152, 1270, 1272, 1340, 1356, 1422, 1536, 1542, 1578 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..50.

FORMULA

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

EXAMPLE

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

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.

MATHEMATICA

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 *)

CROSSREFS

Cf. A000040, A001358, A061358, A100949.

Sequence in context: A031256 A032730 A275274 * A084418 A226133 A125971

Adjacent sequences:  A131831 A131832 A131833 * A131835 A131836 A131837

KEYWORD

nonn

AUTHOR

Jonathan Vos Post, Oct 04 2007

EXTENSIONS

Data corrected by Giovanni Resta, Jun 19 2016

STATUS

approved

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Last modified December 6 17:05 EST 2021. Contains 349567 sequences. (Running on oeis4.)