A352963 What remains from the sequence of positive integers (A000027) when all prime sums of two successive digits are erased.

7, 10, 13, 15, 17, 18, 22, 24, 26, 27, 31, 33, 35, 36, 44, 45, 54, 55, 57, 59, 60, 62, 63, 64, 66, 68, 69, 71, 72, 73, 75, 77, 78, 81, 82, 84, 86, 87, 80, 91, 93, 95, 96, 97, 99, 100, 10, 10, 108, 2, 27, 3, 133, 35, 1337, 39, 0, 15, 153, 1555, 57, 59, 0, 17773, 75, 77, 178, 179, 180, 188, 18, 1887, 90

Offset

1,1

Comments

After an erasure, we start reading again what is left, from the beginning, in order to spot the next pair of successive digits that will be erased. Those two digits can span a comma or a void.

Links

Table of n, a(n) for n=1..73.

Eric Angelini, La Poussette, personal blog (in French), April 2022.

Example

We start with 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, ...
as 1 + 2 = 3 (prime) we erase those two digits; we are left with:
3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, ...
as 3 + 4 = 7 (prime) we erase those two digits; we are left with:
5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, ...
as 5 + 6 = 11 (prime) we erase those two digits; we are left with:
7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, ...
as 8 + 9 = 17 (prime) we erase those two digits; we are left with:
7, 10, 11, 12, 13, 14, 15, 16, 17, ...
as 1 + 1 = 2 (prime) we erase those two digits; we are left with:
7, 10, 12, 13, 14, 15, 16, 17, ...
as 1 + 2 = 3 (prime) we erase those two digits; we are left with:
7, 10, 13, 14, 15, 16, 17, ...
as 1 + 4 = 5 (prime) we erase those two digits; we are left with:
7, 10, 13, 15, 16, 17, ...
as 1 + 6 = 7 (prime) we erase those two digits; we are left with:
7, 10, 13, 15, 17, ... etc.
What remains is this sequence.

Crossrefs

Cf. A000027, A000040.

Sequence in context: A345478 A295797 A153040 * A024888 A226567 A184106

Adjacent sequences: A352960 A352961 A352962 * A352964 A352965 A352966

Keyword

base,nonn

Author

Eric Angelini and Carole Dubois, Apr 11 2022

Status

approved