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A339556
Number of subsets of the first n primes whose elements have a prime root-mean-square.
0
1, 2, 3, 4, 5, 6, 11, 16, 19, 30, 41, 54, 69, 106, 177, 272, 397, 686, 1299, 2416, 4225, 7196, 11701, 20352, 36305, 70134, 132721, 248722, 473391, 894318, 1674923, 3054022, 5452067, 9626552, 16696543, 29086462, 51830095, 96887612, 192393735, 397875694
OFFSET
1,2
LINKS
Eric Weisstein's World of Mathematics, Root-Mean-Square
EXAMPLE
a(7) = 11 subsets: {2}, {3}, {5}, {7}, {11}, {13}, {17}, {7, 17}, {5, 7, 17}, {7, 13, 17} and {5, 7, 11, 17}.
KEYWORD
nonn
AUTHOR
Ilya Gutkovskiy, Dec 08 2020
EXTENSIONS
a(10)-a(40) from Alois P. Heinz, Dec 08 2020
STATUS
approved