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A220162 Smallest prime expressible as 2p + 3q (p, q primes) exactly in n ways. 1
13, 19, 47, 43, 97, 127, 151, 227, 223, 271, 467, 487, 571, 601, 523, 691, 727, 967, 853, 1151, 1051, 1213, 1451, 1303, 1607, 1579, 1523, 1867, 1531, 1951, 1999, 1987, 2239, 2647, 2243, 2663, 2767, 2683, 3037, 2917, 3187, 3259, 3407, 3673, 3823, 3797, 4231 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Zak Seidov, Table of n, a(n) for n = 1..200

EXAMPLE

13 = 2*2 + 3*3,

19 = 2*2 + 3*5 = 2*5 + 3*3,

47 = 2*7 + 3*11 = 2*13 + 3*7 = 2*19 + 3*3.

MATHEMATICA

mx = 50000; s = Table[0, {mx}]; Do[p = Prime[k]; Do[a = 2 Prime[i] + 3 p ; s[[a]]++, {i, PrimePi[(mx - 3 p)/2]}], {k, PrimePi[(mx - 4)/3]}]; ta = Table[s[[Prime[k]]], {k, PrimePi[mx ]}]; Table[{k, Prime[Position[ta, k][[1, 1]]]}, {k, 200}] (* for bfile *)

CROSSREFS

Cf. A079026, A219955, A219956, A219957, A219958, A219959.

Sequence in context: A174152 A103176 A156940 * A248483 A274424 A180528

Adjacent sequences:  A220159 A220160 A220161 * A220163 A220164 A220165

KEYWORD

nonn

AUTHOR

Zak Seidov, Dec 06 2012

STATUS

approved

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Last modified January 24 03:35 EST 2018. Contains 298115 sequences.