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A043294 Sum of digits of binomial(2n,n). 1
2, 6, 2, 7, 9, 15, 12, 18, 20, 31, 21, 25, 11, 18, 27, 27, 27, 33, 39, 54, 57, 51, 45, 45, 54, 72, 74, 67, 66, 76, 77, 72, 75, 78, 90, 88, 86, 96, 83, 88, 117, 99, 99, 117, 99, 108, 90, 108, 126, 126, 117, 144, 135, 141, 156, 153, 138, 141, 153, 153, 126, 162, 156, 168 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..64.

FORMULA

a(n) = A007953(A000984(n)). - Michel Marcus, Feb 17 2021

EXAMPLE

Binomial(2*6,6)=924 and 9+2+4=15 hence a(6)=15.

PROG

(PARI) a(n) = sumdigits(binomial(2*n, n)); \\ Michel Marcus, Feb 17 2021

CROSSREFS

Cf. A000984, A007953.

Sequence in context: A086359 A091944 A069936 * A033641 A153190 A010240

Adjacent sequences:  A043291 A043292 A043293 * A043295 A043296 A043297

KEYWORD

base,easy,nonn

AUTHOR

Benoit Cloitre, Mar 24 2002

EXTENSIONS

Typo in data corrected by Michel Marcus, Feb 17 2021

STATUS

approved

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Last modified December 5 10:11 EST 2021. Contains 349543 sequences. (Running on oeis4.)