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A235692 Semiprimes which have one or more occurrences of exactly four different digits. 2
1027, 1037, 1042, 1043, 1046, 1047, 1057, 1059, 1067, 1073, 1079, 1082, 1094, 1203, 1205, 1207, 1234, 1238, 1243, 1247, 1253, 1257, 1263, 1267, 1273, 1285, 1286, 1293, 1294, 1306, 1329, 1345, 1346, 1347, 1349, 1354, 1357, 1369, 1379, 1382, 1385, 1387, 1389 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

The first term having a repeated digit is 10027.

LINKS

Table of n, a(n) for n=1..43.

PROG

(PARI)

list(lim)=my(v=List(), t); forprime(p=2, sqrt(lim), t=p; forprime(q=p, lim\t, listput(v, t*q))); vecsort(Vec(v)) \\ From A001358

b=list(15000); s=[]; for(n=1, #b, if(#vecsort(eval(Vec(Str(b[n]))), , 8)==4, s=concat(s, b[n]))); s

CROSSREFS

Cf. A235690, A235691, A235693-A235696.

Cf. A235154-A235161.

Sequence in context: A229000 A168153 A246245 * A247947 A066133 A119455

Adjacent sequences:  A235689 A235690 A235691 * A235693 A235694 A235695

KEYWORD

nonn,base

AUTHOR

Colin Barker, Jan 14 2014

STATUS

approved

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Last modified January 25 23:08 EST 2020. Contains 331270 sequences. (Running on oeis4.)