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A300737
Numbers of the form (k*i + 1)*(k*j - 1) with i, j >= 1 and k >= 2.
1
3, 5, 7, 8, 9, 11, 13, 14, 15, 17, 19, 20, 21, 23, 24, 25, 26, 27, 29, 31, 32, 33, 35, 37, 38, 39, 41, 43, 44, 45, 47, 48, 49, 50, 51, 53, 54, 55, 56, 57, 59, 61, 62, 63, 64, 65, 67, 68, 69, 71, 73, 74, 75, 77, 79, 80, 81, 83, 84, 85, 86, 87, 89, 90, 91, 92, 93, 95, 97, 98, 99, 101
OFFSET
1,1
PROG
(PARI) limit=100; v=vector(limit); for(n=0, limit, for(k=2, floor(limit^(1/2)), for(i=1, limit/k, for(j=1, limit/k, if(n==(k*i+1)*(k*j-1), v[n]=1, ))))); for(n=1, limit, if(v[n], print1(n", ")))
CROSSREFS
Cf. A056868.
Sequence in context: A060462 A072668 A249433 * A062958 A295075 A184996
KEYWORD
nonn
AUTHOR
Gionata Neri, Mar 11 2018
STATUS
approved