OFFSET
0,6
FORMULA
a(n) = # { x in A031157 | 2^n < x < 2^(n+1) }. - M. F. Hasler, Nov 24 2021
EXAMPLE
a(6) = 4 since there are 4 prime lucky numbers (67, 73, 79, and 127) between 2^6 = 64 and 2^7 = 128.
CROSSREFS
KEYWORD
nonn,more
AUTHOR
Kevin P. Thompson, Nov 22 2021
STATUS
approved