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A182477
Primes of the form p*q*r + 2, where p, q and r are distinct primes.
0
107, 167, 197, 233, 257, 347, 359, 401, 431, 457, 467, 557, 563, 617, 647, 653, 743, 761, 797, 863, 887, 937, 971, 1087, 1097, 1187, 1223, 1237, 1283, 1297, 1409, 1481, 1493, 1549, 1553, 1583, 1597, 1601, 1607, 1637, 1697, 1871, 1889, 1907, 1949, 2003, 2017
OFFSET
1,1
FORMULA
{A007304(n)+2} INTERSECTION {A000040}.
EXAMPLE
107 = 3*5*7+2.
MATHEMATICA
mx = 50; ps = Prime[Range[2, mx + 1]]; t = Table[ps[[i]]*ps[[j]]*ps[[k]] + 2, {i, mx}, {j, i + 1, mx}, {k, j + 1, mx}]; Select[Union[Flatten[t]], # <= 3*5*ps[[-1]] + 2 && PrimeQ[#] &] (* T. D. Noe, May 01 2012 *)
CROSSREFS
Cf. A115267.
Sequence in context: A168475 A142662 A178416 * A229570 A107215 A142142
KEYWORD
nonn
AUTHOR
Alex Ratushnyak, May 01 2012
STATUS
approved