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A261449 Prime numbers whose decimal digits contain a total of two loops. 0
83, 109, 149, 181, 199, 269, 281, 283, 349, 383, 401, 419, 439, 443, 461, 463, 467, 479, 491, 509, 569, 587, 599, 601, 607, 619, 641, 643, 647, 659, 661, 691, 709, 769, 787, 811, 821, 823, 827, 853, 857, 877, 907, 919, 929, 941, 947, 967, 991, 997, 1019, 1039 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Of the digits, 0 through 9, {0, 4, 6, 9} have one loop, 8 has two loops, and all the rest have none. - Robert G. Wilson v, Aug 20 2015

LINKS

Table of n, a(n) for n=1..52.

EXAMPLE

83 is the first term of the sequence. The digit 8 contains two closed curves.

MATHEMATICA

Select[Prime@ Range@ 200, 2 == Total[{ 1, 0, 0, 0, 1, 0, 1, 0, 2, 1}[[1 + IntegerDigits@ #]]]&] (* Giovanni Resta, Aug 19 2015 *)

CROSSREFS

Cf. A001729, A190222, A001743, A001744, A001745, A249572.

Sequence in context: A031412 A033252 A347226 * A288880 A126117 A096279

Adjacent sequences:  A261446 A261447 A261448 * A261450 A261451 A261452

KEYWORD

nonn,less,easy,base

AUTHOR

Altug Alkan, Aug 19 2015

EXTENSIONS

More terms from Giovanni Resta, Aug 19 2015

STATUS

approved

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Last modified November 28 22:01 EST 2021. Contains 349415 sequences. (Running on oeis4.)