A084724 - OEIS

A084724

Beginning with 2, the smallest even number greater than the previous term such that every partial product + 1 is a prime.

2, 6, 8, 12, 16, 18, 20, 22, 26, 36, 42, 44, 100, 120, 124, 162, 168, 174, 192, 218, 272, 278, 338, 364, 380, 392, 502, 512, 532, 560, 594, 614, 698, 790, 814, 838, 922, 938, 1072, 1082, 1092, 1102, 1146, 1182, 1256, 1354, 1360, 1484, 1508, 1566, 1662, 1690

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OFFSET

1,1

LINKS

Harvey P. Dale, Table of n, a(n) for n = 1..100

MATHEMATICA

ppp[{p_, a_}]:=Module[{n=a+2}, While[!PrimeQ[p*n+1], n=n+2]; {p*n, n}]; NestList[ ppp, {2, 2}, 60][[All, 2]] (* Harvey P. Dale, Aug 12 2017 *)

CROSSREFS

Cf. A083566, A084723, A084725.

Sequence in context: A083769 A057656 A247066 * A283233 A189400 A285342

Adjacent sequences: A084721 A084722 A084723 * A084725 A084726 A084727

KEYWORD

nonn

AUTHOR

Amarnath Murthy and Meenakshi Srikanth (menakan_s(AT)yahoo.com), Jun 13 2003

EXTENSIONS

More terms from David Wasserman, Jan 03 2005

STATUS

approved