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A172425
Pentagonal pyramidal numbers which are the sum of two other such numbers: A002411(k) = A002411(i)+A002411(j) with i,j>0.
3
37926, 279046, 2514726, 34797726, 71254566, 348145726, 566225926, 606245926, 828497488, 1206646551, 8750871976, 11481404326, 21078151200, 28120290876, 62963640936, 75128827176, 77009692800, 96868002726, 120282238710, 147061923750, 165998399400, 297022824126, 325443925926, 416397477888
OFFSET
1,1
COMMENTS
The corresponding indices are listed in A172437. This answers a question posed in A133459.
LINKS
FORMULA
a(n) = A002411(A172437(n))
PROG
(PARI) for(n=1, 99999, for(m=1, n-1, isA002411(A002411(n)-A002411(m)) | next; print1(A002411(n)", "); break)) /* needs A002411() and isA240011() */
CROSSREFS
Sequence in context: A250150 A345818 A102332 * A224906 A364309 A168628
KEYWORD
nonn
AUTHOR
M. F. Hasler, Nov 20 2010
STATUS
approved