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A167390 Partial sums of A137442. 1
1, 3, 7, 10, 19, 24, 40, 46, 71, 78, 114, 122, 171, 181, 245, 256, 337, 349, 449, 462, 583, 597, 741, 756, 925, 942, 1138, 1156, 1381, 1400, 1656, 1676, 1965, 1986, 2310, 2332, 2693, 2716, 3116, 3140, 3581, 3607, 4091, 4118, 4647, 4675, 5251, 5280, 5905, 5935 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,2
LINKS
FORMULA
Set R(N)=N+ROUND(SQRT(N),0), S(N)=FLOOR(SQRT(R(N))), U(N)=R(N)*(R(N)+1)/2-S(N)*(S(N)+1)*(S(N)+.5)/3, T(N)=CEILING(N/2), then a(N)=T(N)*(1+T(N)*(3+2*T(N)))/6+U(FLOOR(N/2))
EXAMPLE
a(14)=1+2+4+3+9+5+16+6+25+7+36+8+49+10=181
CROSSREFS
Sequence in context: A365931 A024330 A069153 * A000223 A366044 A031328
KEYWORD
nonn
AUTHOR
Gerald Hillier, Nov 02 2009
EXTENSIONS
Terms a(15) and above from Gerald Hillier, Jan 06 2022
STATUS
approved

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Last modified March 28 14:38 EDT 2024. Contains 371254 sequences. (Running on oeis4.)