A256354 Composites in base 10 that remain composite in exactly four bases b, 2 <= b <= 10, expansions interpreted as decimal numbers.

115, 2563, 3523, 5071, 9193, 10873, 12223, 12811, 13231, 15775, 19111, 20203, 23089, 25831, 27007, 28171, 34189, 39859, 40033, 43361, 55033, 57871, 58813, 74371, 84253, 89377, 93043, 95833, 101683, 117001, 125359, 126673, 128953, 131029, 134527, 137467, 138193

Offset

1,1

Links

Sebastian Petzelberger, Table of n, a(n) for n = 1..10000

Carlos Rivera, PP&P Puzzle 24: Primes in several bases

Crossrefs

Cf. A052026, A256350-A256356, A038537, A052027-A052033, A084482, A236356.

Sequence in context: A258673 A287430 A256889 * A005466 A279451 A056101

Adjacent sequences: A256351 A256352 A256353 * A256355 A256356 A256357

Keyword

nonn,base

Author

Sebastian Petzelberger, Mar 25 2015

Status

approved