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A155775 Indices j in A000040 such that j is an odd composite and the distinct digits of the prime A000040(j) are in increasing order. 0
9, 15, 33, 35, 39, 55, 57, 69, 75, 77, 91, 203, 205, 207, 209, 219, 237, 247, 249, 355, 365, 391, 405, 483, 633, 749, 1475, 1501, 1515, 1595, 1605, 1615, 1631, 2611, 2637, 2829, 11603, 11803, 13479, 20797, 20891, 95375 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

These are the odd composites n (A071904) such that the digits of prime(n) are strictly increasing. The latter defines a subsequence of A028864, which lists primes with nondecreasing digits. - R. J. Mathar, Jan 30 2009

LINKS

Table of n, a(n) for n=1..42.

EXAMPLE

If odd number=n=9 and prime(9)=23, then 2<3 and 9=a(1). If odd number=n=15 and prime(15)=47, then 4<7 and 15=a(2). If odd number=n=33 and prime(33)=137, then 1<3<7 and 33=a(3), etc.

CROSSREFS

Cf. A000040, A002808, A155079.

Sequence in context: A108637 A091296 A107076 * A228096 A111148 A125216

Adjacent sequences:  A155772 A155773 A155774 * A155776 A155777 A155778

KEYWORD

nonn,base

AUTHOR

Juri-Stepan Gerasimov, Jan 27 2009

EXTENSIONS

Corrected and extended by R. J. Mathar, Jan 30 2009

Better definition from Omar E. Pol, Jan 31 2009

STATUS

approved

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Last modified December 4 05:56 EST 2021. Contains 349470 sequences. (Running on oeis4.)