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A056808 Members of A055932 which are not least prime signatures (cf. A025487). 6
18, 54, 90, 108, 150, 162, 270, 300, 324, 450, 486, 540, 600, 630, 648, 750, 810, 972, 1050, 1200, 1350, 1458, 1470, 1500, 1620, 1890, 1944, 2100, 2250, 2400, 2430, 2700, 2916, 2940, 3000, 3150, 3240, 3750, 3780, 3888, 4050, 4200, 4374, 4410, 4500, 4800 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Michael De Vlieger, Table of n, a(n) for n = 1..10000

EXAMPLE

18 = 2*3*3 and all prime divisors are consecutive primes but the least prime signature is 12 = 2*2*3; so a(1) = 18.

MATHEMATICA

With[{nn = 4800}, Select[Range[2, nn], And[#1 != Times @@ MapIndexed[Prime[First@ #2]^#1 &, Sort[#3, Greater]], Last[#2] == Prime@ Length[#2]] & @@ Apply[Join, {{#1}, Transpose@ #2}] & @@ {#, FactorInteger[#]} &] ] (* Michael De Vlieger, Feb 06 2020 *)

CROSSREFS

Cf. A025487, A055932.

Sequence in context: A068396 A205874 A044120 * A044501 A163758 A232546

Adjacent sequences:  A056805 A056806 A056807 * A056809 A056810 A056811

KEYWORD

easy,nonn

AUTHOR

Alford Arnold, Aug 22 2000

EXTENSIONS

More terms from Larry Reeves (larryr(AT)acm.org), Nov 28 2000

STATUS

approved

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Last modified October 30 03:24 EDT 2020. Contains 338076 sequences. (Running on oeis4.)