A227951
The number of consecutive values juxtaposed to obtain the value A227949(n).
Original entry on oeis.org
2, 2, 4, 2, 4, 2, 2, 4, 2, 4, 2, 10, 8, 2, 2, 40, 2, 14, 38, 2, 2, 2, 158, 20, 2, 52, 38, 2, 4, 60, 34, 652, 2, 8, 20
Offset: 1
A227949(12)=100999897969594939291, so a(12)=10 as this concatenates the 10 numbers from 100 down to 91.
A227950
Number of decimal digits in the increasing sequence of primes obtainable by concatenating successive decrements from some power of 10.
Original entry on oeis.org
3, 5, 5, 7, 9, 11, 13, 13, 15, 17, 19, 21, 25, 27, 53, 81, 85, 183, 191, 307, 377, 409, 475, 541, 565, 885, 1065, 1399, 1489, 2653, 4523, 4565, 5773, 7777, 14281
Offset: 1
1000999998997 is one of the primes described and provides a value of 13 in this sequence, with 1000000999999 providing the other (A227949(7) and A227949(8), in opposite order for the purposes of the FORMULA at that sequence (technically)).
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