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This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A297709 Table read by antidiagonals: Let b be the number of digits in the binary expansion of n. Then T(n,k) is the k-th odd prime p such that the binary digits of n match the primality of the b consecutive odd numbers beginning with p (or 0 if no such k-th prime exists).

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%I A297709 #28 Jan 25 2022 13:02:27
%S A297709 3,5,7,7,13,3,11,19,5,23,13,23,11,31,7,17,31,17,47,13,5,19,37,29,53,
%T A297709 19,11,3,23,43,41,61,37,17,0,89,29,47,59,73,43,29,0,113,23,31,53,71,
%U A297709 83,67,41,0,139,31,19,37,61,101,89,79,59,0,181,47,43,7,41,67
%N A297709 Table read by antidiagonals: Let b be the number of digits in the binary expansion of n. Then T(n,k) is the k-th odd prime p such that the binary digits of n match the primality of the b consecutive odd numbers beginning with p (or 0 if no such k-th prime exists).
%C A297709 For each n >= 1, row n is the union of rows 2n and 2n+1.
%C A297709 Rows with no nonzero terms: 15, 21, 23, 28, 30, 31, ...
%C A297709 Rows whose only nonzero term is 3: 7, 14, 29, 59, 118, 237, 475, 950, 1901, 3802, 7604, ...
%C A297709 Rows whose only nonzero term is 5: 219, 438, 877, 1754, 3508, 7017, 14035, ...
%C A297709 For j = 2, 3, 4, ..., respectively, the first row whose only nonzero term is prime(j) is 7, 219, 2921, ...; is there such a row for every odd prime?
%e A297709 13 = 1101_2, so row n=13 lists the odd primes p such that the four consecutive odd numbers p, p+2, p+4, and p+6 are prime, prime, composite, and prime, respectively; these are the terms of A022004.
%e A297709 14 = 1110_2, so row n=14 lists the odd primes p such that p, p+2, p+4, and p+6 are prime, prime, prime, and composite, respectively; since there is only one such prime (namely, 3), there is no such 2nd, 3rd, 4th, etc. prime, so the terms in row 14 are {3, 0, 0, 0, ...}.
%e A297709 15 = 1111_2, so row n=15 would list the odd primes p such that p, p+2, p+4, and p+6 are all prime, but since no such prime exists, every term in row 15 is 0.
%e A297709 Table begins:
%e A297709   n in base|                    k                   |  OEIS
%e A297709   ---------+----------------------------------------+sequence
%e A297709   10     2 |   1    2    3    4    5    6    7    8 | number
%e A297709   =========+========================================+========
%e A297709    1     1 |   3    5    7   11   13   17   19   23 | A065091
%e A297709    2    10 |   7   13   19   23   31   37   43   47 | A049591
%e A297709    3    11 |   3    5   11   17   29   41   59   71 | A001359
%e A297709    4   100 |  23   31   47   53   61   73   83   89 | A124582
%e A297709    5   101 |   7   13   19   37   43   67   79   97 | A029710
%e A297709    6   110 |   5   11   17   29   41   59   71  101 | A001359*
%e A297709    7   111 |   3    0    0    0    0    0    0    0 |
%e A297709    8  1000 |  89  113  139  181  199  211  241  283 | A083371
%e A297709    9  1001 |  23   31   47   53   61   73   83  131 | A031924
%e A297709   10  1010 |  19   43   79  109  127  163  229  313 |
%e A297709   11  1011 |   7   13   37   67   97  103  193  223 | A022005
%e A297709   12  1100 |  29   59   71  137  149  179  197  239 | A210360*
%e A297709   13  1101 |   5   11   17   41  101  107  191  227 | A022004
%e A297709   14  1110 |   3    0    0    0    0    0    0    0 |
%e A297709   15  1111 |   0    0    0    0    0    0    0    0 |
%e A297709   16 10000 | 113  139  181  199  211  241  283  293 | A124584
%e A297709   17 10001 |  89  359  389  401  449  479  491  683 | A031926
%e A297709   18 10010 |  31   47   61   73   83  151  157  167 |
%e A297709   19 10011 |  23   53  131  173  233  263  563  593 | A049438
%e A297709   20 10100 |  19   43   79  109  127  163  229  313 |
%e A297709   21 10101 |   0    0    0    0    0    0    0    0 |
%e A297709   22 10110 |   7   13   37   67   97  103  193  223 | A022005
%e A297709   23 10111 |   0    0    0    0    0    0    0    0 |
%e A297709   24 11000 | 137  179  197  239  281  419  521  617 |
%e A297709   25 11001 |  29   59   71  149  269  431  569  599 | A049437*
%e A297709   26 11010 |  17   41  107  227  311  347  461  641 |
%e A297709   27 11011 |   5   11  101  191  821 1481 1871 2081 | A007530
%e A297709   28 11100 |   0    0    0    0    0    0    0    0 |
%e A297709   29 11101 |   3    0    0    0    0    0    0    0 |
%e A297709   30 11110 |   0    0    0    0    0    0    0    0 |
%e A297709   31 11111 |   0    0    0    0    0    0    0    0 |
%e A297709 *other than the referenced sequence's initial term 3
%e A297709 .
%e A297709 Alternative version of table:
%e A297709 .
%e A297709   n in base|primal-|               k              |  OEIS
%e A297709   ---------+  ity  +------------------------------+  seq.
%e A297709   10     2 |pattern|   1    2    3    4    5    6 | number
%e A297709   =========+=======+==============================+========
%e A297709    1     1 | p     |   3    5    7   11   13   17 | A065091
%e A297709    2    10 | pc    |   7   13   19   23   31   37 | A049591
%e A297709    3    11 | pp    |   3    5   11   17   29   41 | A001359
%e A297709    4   100 | pcc   |  23   31   47   53   61   73 | A124582
%e A297709    5   101 | pcp   |   7   13   19   37   43   67 | A029710
%e A297709    6   110 | ppc   |   5   11   17   29   41   59 | A001359*
%e A297709    7   111 | ppp   |   3    0    0    0    0    0 |
%e A297709    8  1000 | pccc  |  89  113  139  181  199  211 | A083371
%e A297709    9  1001 | pccp  |  23   31   47   53   61   73 | A031924
%e A297709   10  1010 | pcpc  |  19   43   79  109  127  163 |
%e A297709   11  1011 | pcpp  |   7   13   37   67   97  103 | A022005
%e A297709   12  1100 | ppcc  |  29   59   71  137  149  179 | A210360*
%e A297709   13  1101 | ppcp  |   5   11   17   41  101  107 | A022004
%e A297709   14  1110 | pppc  |   3    0    0    0    0    0 |
%e A297709   15  1111 | pppp  |   0    0    0    0    0    0 |
%e A297709   16 10000 | pcccc | 113  139  181  199  211  241 | A124584
%e A297709   17 10001 | pcccp |  89  359  389  401  449  479 | A031926
%e A297709   18 10010 | pccpc |  31   47   61   73   83  151 |
%e A297709   19 10011 | pccpp |  23   53  131  173  233  263 | A049438
%e A297709   20 10100 | pcpcc |  19   43   79  109  127  163 |
%e A297709   21 10101 | pcpcp |   0    0    0    0    0    0 |
%e A297709   22 10110 | pcppc |   7   13   37   67   97  103 | A022005
%e A297709   23 10111 | pcppp |   0    0    0    0    0    0 |
%e A297709   24 11000 | ppccc | 137  179  197  239  281  419 |
%e A297709   25 11001 | ppccp |  29   59   71  149  269  431 | A049437*
%e A297709   26 11010 | ppcpc |  17   41  107  227  311  347 |
%e A297709   27 11011 | ppcpp |   5   11  101  191  821 1481 | A007530
%e A297709   28 11100 | pppcc |   0    0    0    0    0    0 |
%e A297709   29 11101 | pppcp |   3    0    0    0    0    0 |
%e A297709   30 11110 | ppppc |   0    0    0    0    0    0 |
%e A297709   31 11111 | ppppp |   0    0    0    0    0    0 |
%e A297709 .
%e A297709      *other than the referenced sequence's initial term 3
%Y A297709 Cf. A001359, A007530, A022004, A022005, A029710, A031924, A031926, A049437, A049438, A049591, A065091, A124582, A083371, A124584, A210360.
%K A297709 nonn,tabl
%O A297709 1,1
%A A297709 _Jon E. Schoenfield_, Apr 15 2018