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 A281020 Numbers with a prime number of raised dots in their Braille representation. 1
 0, 1, 4, 6, 8, 12, 13, 15, 19, 21, 31, 47, 51, 67, 70, 74, 76, 78, 87, 91, 100, 104, 106, 108, 111, 127, 137, 140, 144, 146, 148, 157, 160, 164, 166, 168, 172, 173, 175, 177, 179, 180, 184, 186, 188, 197, 202, 203, 205, 207, 209, 217, 220, 224, 226, 228, 230, 234, 236, 238 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,3 LINKS Indranil Ghosh, Table of n, a(n) for n = 1..10000 Indranil Ghosh, Braille Numerals EXAMPLE 67 is in the sequence. 67, as evident from the link uploaded above, has 11 raised dots ("o") in its Braille representation and 11 is prime. PROG (Python) from sympy import isprime B=[3, 1, 2, 2, 3, 2, 3, 4, 3, 2] def a(n):     s=0     for i in str(n):         s+=B[int(i)]     return s+4 i=0 j=1 while j<=10000:     if isprime(a(i))==True :         print str(j)+" "+str(i)         j+=1     i+=1 CROSSREFS Cf. A072283, A281015, A281017. Sequence in context: A031359 A274790 A179852 * A110606 A346124 A241124 Adjacent sequences:  A281017 A281018 A281019 * A281021 A281022 A281023 KEYWORD nonn,base AUTHOR Indranil Ghosh, Jan 13 2017 STATUS approved

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Last modified September 21 01:46 EDT 2021. Contains 347596 sequences. (Running on oeis4.)